all: trim the history essays out of the longest comments

From the audit (#5179). Ten comment blocks narrated how the code got here:
milestone numbers, earlier values, the operator's verdict on an old design.
Each now says what the code does and why, and the history stays in git,
Scribe and docs/sync.md. The protocol-version comment in sync.py points at
docs/sync.md's policy section, which already lists every bump.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

frontend/src/notes/blocks.ts

@@ -110,28 +110,18 @@ export function plusTask(blocks: EditorBlock[]): { blocks: EditorBlock[]; focus:
 }
 
 /**
- * Re-read ONE prose block for `- [ ] ` lines somebody typed by hand.
+ * Re-read ONE prose block for `- [ ] ` lines somebody typed by hand, so a marker
+ * typed in the editor becomes an item without closing and reopening the note.
  *
- * `splitBlocks` runs once, when the editor opens. After that the blocks are the state
- * and nothing reads the body again — every edit travels the other way, through
- * `joinBlocks`. So a marker typed by hand stayed literal text on screen until the note
- * was closed and reopened, even though it was already a real item in storage and the
- * card was already drawing a checkbox for it. The editor was the only place that
- * disagreed.
+ * On blur, and only the block being left: re-splitting on a keystroke would move the
+ * caret, and converting the moment `- [ ]` is complete would catch an item with no
+ * text yet.
  *
- * ON BLUR, and only the block being left. There is no good moment to convert while
- * someone is typing: re-splitting on a keystroke moves the caret out of the word being
- * written, and converting the instant `- [ ]` is complete does it before the item has
- * any text. Blur is the one moment the person has demonstrably finished with the block,
- * so a re-split costs no caret and cannot catch a half-typed line.
+ * Returns THE SAME ARRAY when there was nothing to promote; the caller relies on that
+ * to leave the ref alone, so a blur that changed nothing doesn't re-key every field.
  *
- * Returns THE SAME ARRAY, not an equal copy, when there was nothing to promote — the
- * caller leans on that to leave the ref alone, and a blur that changed nothing must not
- * re-key every field below it.
- *
- * Non-canonical markers (`- [X]`, an odd bullet) come back canonical, exactly as they
- * would have on reopen. That is the only case where this changes the body rather than
- * only the way it is drawn.
+ * Non-canonical markers (`- [X]`, an odd bullet) come back canonical, as they would on
+ * reopen.
  */
 export function promoteTasks(blocks: EditorBlock[], index: number): EditorBlock[] {
   const block = blocks[index];

frontend/src/notes/colors.ts

@@ -36,29 +36,12 @@ export const NOTE_SWATCH_CLASSES: Record<NoteColor, string> = {
 };
 
 // A chip's SHELL: its fill and its hairline edge, keyed by the colour vocabulary. The
-// INK is not here — see TAG_TEXT_CLASSES, which one table now serves both a chip's text
-// and a `#tag` left in the prose. Compose the two with `labelChipClasses`.
+// ink is TAG_TEXT_CLASSES; `labelChipClasses` composes the two.
 //
-// THE RING IS NOT DECORATION. A chip's fill measures 1.02-1.26 against the card in
-// light and 1.02-1.73 in dark — that is to say, very nearly nothing. The pill's shape
-// is the edge; the fill only tints it. (Dark red is the extreme at 1.02, which is
-// invisible: without the ring that chip would be loose text.) An edge holds the shape
-// against any background, where shifting the fill only moves which card it collides
-// with.
-//
-// AT 65%, NOT 60%, AND SOLVED FOR RATHER THAN GUESSED. 0.60 was chosen against a worst
-// case that no longer exists — a chip sitting on a card of its own colour, back when a
-// note took its first tag's fill. Against the one card surface (M315) the ring is the
-// ink at alpha over a known fill, so the alpha that clears the 3:1 of WCAG 1.4.11 for
-// all ten hues can simply be solved: 0.60 gives 2.75-3.82 in light and misses for six
-// of them, 0.65 gives 3.03-4.36 and misses for none. Dark is 4.52-5.76. 0.80 was the
-// number the old comment named as the fallback and it is more than is needed — it
-// draws a hard outline where a hairline does the job.
-//
-// `default`'s ring was `black/10 dark:white/15` here and the ink at alpha on the phone —
-// 1.36 against its own fill in light against Compose's 3.21, so the two surfaces were
-// drawing visibly different pills for the same chip. It is the ink at 65% on both now,
-// like every other key: one rule for ten hues, not nine and an exception.
+// The ring is what gives the pill its shape: a chip's fill measures only 1.02-1.73
+// against the card. It is the ink at 65%, the lowest alpha that clears WCAG 1.4.11's
+// 3:1 for all ten hues on the one card surface (light 3.03-4.36, dark 4.52-5.76).
+// `default` follows the same rule as every other key.
 //
 // Mirrored in NoteTint.kt as `chipBackground` and `chipBorder` / CHIP_EDGE_ALPHA.
 export const LABEL_CHIP_SHELL: Record<NoteColor, string> = {
@@ -74,26 +57,13 @@ export const LABEL_CHIP_SHELL: Record<NoteColor, string> = {
   gray: "bg-neutral-200 dark:bg-neutral-700 ring-1 ring-inset ring-neutral-800/65 dark:ring-neutral-200/65",
 };
 
-// THE INK A TAG IS DRAWN IN — one table, for a `#tag` left in the prose AND for a
-// chip's text. It was two, and the split was real while it lasted: a chip carried its
-// own `-100` fill and could afford `-700`, while inline text sat on whatever the card
-// was, which included a gray-tagged card at `neutral-200` where `-700` measured 3.98
-// (green), 4.11 (orange) and 4.34 (teal) — all under the 4.5 body text needs. One step
-// deeper cleared every fill at once, so inline got `-800` and the chip kept `-700`.
-//
-// M315 removed the twenty card fills the split was solving for, and this is the payoff:
-// against ONE card surface both jobs can take the same value. `-800`/`-300` is the one
-// they take, and the direction is deliberate — the inline token is the common case
-// (since M311 a tag whose text is in the body is drawn where it was typed and NOT
-// repeated as a chip), so collapsing onto the inline column leaves what is seen most
-// exactly as it was, and moves only the chip. The chip is strictly better for it:
+// THE INK A TAG IS DRAWN IN — one table, for a `#tag` left in the prose and for a
+// chip's text. `-800` in light and `-300` in dark clear body-text contrast in both
+// places:
 //
 //                     inline, on the card        as a chip, on its own fill
-//   light `-800`      7.09 - 15.13               6.37 - 12.01   (was 4.52 - 8.23)
-//   dark  `-300`      9.45 - 14.23               8.23 - 11.88   (unchanged)
-//
-// Dark needed no decision at all: the two tables were already the same value for all
-// ten hues, which is on its own most of the argument that one table was always enough.
+//   light `-800`      7.09 - 15.13               6.37 - 12.01
+//   dark  `-300`      9.45 - 14.23               8.23 - 11.88
 //
 // Mirrored in NoteTint.kt as `lightTagInk` / `darkTagInk`.
 export const TAG_TEXT_CLASSES: Record<NoteColor, string> = {
@@ -249,33 +219,9 @@ export function resolveLabelColor(label: { name: string; color?: string | null }
 // chips of one colour are the same tag. The chip's text is what says which tag it is.
 
 // ---------------------------------------------------------------------------
-// THE CARD SURFACE — one neutral, no hue, no note involved (M315).
-//
-// This used to be a function of the note: a palette class for a tagged one, a fill
-// generated from the id for the rest. Both are gone. The operator's verdict after
-// four passes at it — "my coloring attempt has failed and nothing looks right… we've
-// tried a lot to make the color work and somehow it never seems to land" — and the
-// diagnosis underneath it is that a card's fill was being asked to carry meaning it
-// could not carry. Nine keys is too few to identify anything on a board of any size,
-// and a generated fill identifies nothing by construction, so a coloured board taught
-// the eye to read hue as significant and then handed it noise.
-//
-// COLOUR NOW LIVES ONLY ON THE TAG — the chip and the inline `#tag`, both of which sit
-// on this one known background from here on. That is a smaller job done properly
-// instead of a larger one done four times.
-//
-// The codebase had already made this argument about the card's EDGE, one level down:
-// the hue-coded border came out as "a neutral line carries no information at all,
-// which is exactly what lets it be structure instead of content". The fill is the same
-// argument at the next size up.
-//
-// THE VALUES. `bg-white dark:bg-neutral-900` — which is exactly what `default` always
-// was, and exactly what the note EDITOR panel has always been (NoteEditor.vue), so
-// this is a collapse onto a surface both other surfaces already used rather than a
-// new colour anybody has to like.
-//
-// Measured against the operator's constraint, "not the same color as their background
-// but close to it":
+// THE CARD SURFACE — one neutral, the same for every note. Colour lives only on tags
+// (the chip and the inline `#tag`); a card's fill can't carry meaning, because nine
+// keys identify nothing on a board of any size. It is the editor panel's surface too.
 //
 //   card vs board   light  #ffffff on #fafafa   1.04
 //                   dark   #171717 on #0a0a0a   1.10
@@ -283,11 +229,7 @@ export function resolveLabelColor(label: { name: string; color?: string | null }
 //                   dark   #404040 on #171717   1.73
 //   body vs card    light  #171717 on #ffffff  17.93   (needs 4.5)
 //                   dark   #fafafa on #171717  17.17
-//   muted vs card   light  #404040 on #ffffff  10.37
-//                   dark   #e5e5e5 on #171717  14.23
 //
-// The fill is deliberately the WEAKEST of those numbers. A card is not separated from
-// the board by its fill and never was — the edge and the shadow do that, which is why
-// 1.04 is enough and why it has to stay near 1: a fill that separated on its own would
-// be a panel, and a board of panels is the wall this whole line of work started from.
+// The fill is deliberately the weakest number: the edge and the shadow separate a card
+// from the board, and a fill strong enough to do it alone would make every card a panel.
 export const NOTE_CARD_SURFACE = "bg-white dark:bg-neutral-900";