refactor: rename package fabledassistant -> scribe (code-only)

Renames src/fabledassistant -> src/scribe and all imports, plus the
default DB name and DB user/password (fabled -> scribe) in config +
compose. 952 refs / 154 files. Reverses the old 'internal name stays
fabledassistant' convention.

Code-only: live databases are still physically named 'fabledassistant'.
Deployed environments must set POSTGRES_DB / POSTGRES_USER (or rename the
DB) since the defaults now resolve to 'scribe'. Repo (FabledScribe), git
host (fabledsword), MCP (fabled-git) and the image name (fabledscribe)
are intentionally unchanged.

ruff check src/ clean locally; CI (typecheck + pytest) is the gate.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/scribe/utils/tags.py

@@ -0,0 +1,11 @@
+import re
+
+_CODE_FENCE_RE = re.compile(r"```[\s\S]*?```|`[^`\n]+`")
+_TAG_RE = re.compile(r"(?<!\w)#([\w][\w-]*(?:/[\w][\w-]*)*)")
+
+
+def extract_tags(body: str) -> list[str]:
+    """Extract #tags from body text, ignoring code blocks."""
+    cleaned = _CODE_FENCE_RE.sub("", body)
+    tags = _TAG_RE.findall(cleaned)
+    return sorted(set(tags))