align(4909d): every rule arm that annotates reads one bar, kb_rule_threshold at 0.70

prompt_rule, pre_tool_rule and write_path_rule now share one settings key,
RULE_FLOOR_KEY = "kb_rule_threshold", default 0.70. The reply backstop keeps
its own 0.80, because there the floor is a stop bar. Moving the shared floor
through tune_retrieval or the Settings form records a tuning event on every
surface that reads it (set_dial, via retrieval_surfaces.sharing_floor), and
the result names the surfaces it carried as `moved_with`. Settings shows one
"Standing-rule confidence threshold" control where it showed three.

Operator ruling (2026-10-05): one shared bar for the rule arms, "especially
since we're only taking the first x number of them" -- the budget limits
what is shown; the bar only decides what is worth ranking. Kept a dial.

Why 0.70, from records read rather than percentiles:
- write_path_rule near-misses at 0.7199-0.72 were all false positives
  (rule 149 against a Lidarr comment, 157 against a retention Svelte file,
  121 against an Archives restore, 164 against a config test, 131 against a
  Go package), so the old 0.72 was not hiding real hits -- but the band does
  noise control on this arm, so dropping 0.02 costs little.
- prompt_rule: the operator set 0.70 by hand on 2026-09-18, after a 0.60
  experiment admitted junk and was reverted. 0.70 is the number with a human
  decision behind it.
- pre_tool_rule lines near 0.68 this session were mostly noise; rising to
  0.70 trims them, and the band still narrows what clears.

Retired keys: kb_promptrule_threshold, kb_toolrule_threshold and
kb_rulehint_threshold are no longer read. Rows an install stored under them
stay in the settings table, inert. On this instance the effective bars move
pre_tool_rule 0.68 -> 0.70, write_path_rule 0.72 -> 0.70, prompt_rule stays
0.70; record_release_defaults writes those per-surface release rows on boot,
so the telemetry shift has an event to explain it.

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

tests/test_settings_defaults_agree.py

@@ -41,7 +41,7 @@ ROOT = pathlib.Path(__file__).resolve().parents[1]
 _SERVICES = ROOT / "src" / "grimoire" / "services"
 _VUE = ROOT / "frontend" / "src" / "views" / "SettingsView.vue"
 
-# THE SIX RETRIEVAL FLOORS live in one registry, so their side of
+# THE RETRIEVAL FLOORS live in one registry, so their side of
 # the pairing is a SURFACE NAME rather than a module constant. That is strictly
 # better for this guard: the surface name is also the telemetry source, so a row
 # here names the same arm the readout does, and a floor that moved cannot be
@@ -49,9 +49,10 @@ _VUE = ROOT / "frontend" / "src" / "views" / "SettingsView.vue"
 _SURFACE_PAIRS = (
     ("auto_inject", "kbInjectThreshold"),
     ("write_path", "kbWritePathThreshold"),
-    ("write_path_rule", "kbRuleHintThreshold"),
-    ("pre_tool_rule", "kbToolRuleThreshold"),
-    ("prompt_rule", "kbPromptRuleThreshold"),
+    # The three rule hints read one bar, so one control serves them.
+    ("write_path_rule", "kbRuleThreshold"),
+    ("pre_tool_rule", "kbRuleThreshold"),
+    ("prompt_rule", "kbRuleThreshold"),
     ("reply_rule", "kbReplyRuleThreshold"),
 )