fix: bounded write-path check with an UNVERIFIED verdict; self-describing close WARNs (GIT-102)

[nTEG-dev]

What

The startup write-path check can no longer go quiet, health shows its verdict, and session_close's WARN says what failed and whether the session was saved (GIT-102).

• Bounded check: checkWritePathWithTimeout() races the startup probe against 10 s. A store that never answers gives the verdict timed out after 10 s, durability UNVERIFIED and a loud stderr warning. If the probe answers later, its real verdict replaces that one, marked late. server.ts uses it on both startup paths (with and without a license key).
• health exposes the last verdict: a write_path field, plus a first line such as Write path: Supabase — … writes are durable (ok, checked …, 327 ms) or Write path: timed out after 10 s, durability UNVERIFIED (NOT OK, …). Before any verdict exists it says not checked yet.
• Self-describing WARN: WARN 1 write failure becomes one line per failing subsystem:

  WARN knowledge graph (triples): 1 of 1 write failed — 1/1 triples failed: Supabase upsert error: 400 - {"code":"22P02",…"invalid input syntax for type uuid: \"t-b4d09cb0\""} · session content stored OK
  

  Every line carries the mandatory clause session content stored OK or session content NOT stored, taken from whether the session row actually landed, not from overall close success.

Found along the way (fixed here, same class)

A probe that failed fast with a network or auth error was deliberately ignored ("out of scope"), so a store refusing every connection logged Write-path OK. The timeout only catches hangs. That case is now its own verdict: unreachable, store unreachable (<error>), durability UNVERIFIED. Counting skipped, there are now six modes: timed_out is the fifth outcome the ticket asked for, and unreachable is the extra one.

How to test

Venue (v1.8.0 setup.sql, vujndhcumgroztfkkdus; production not touched): flow now requires every close WARN to match <subsystem>: N of M writes failed — <cause> · session content (stored OK|NOT stored), and health to carry a Write path: line. The GIT-105 triple 400 provides a real write failure to describe.

	origin/main 1.10.0	This branch
Close WARN	WARN 1 write failure	the line above, which names GIT-105's own cause
health	no write-path verdict	Write path: Supabase — learnings/decisions tables present, writes are durable (ok, …, 327 ms)
Exit	1	0

A store that hangs (local probe, not the venue: a TCP listener that accepts and never answers, used as SUPABASE_URL; health called at 11.5 s):

	origin/main	This branch
health line 1	No tracked effects this session.	Write path: timed out after 10 s, durability UNVERIFIED (NOT OK, checked …, 10018 ms)
stderr	nothing: the probe is still pending	⚠️ [gitmem] WRITE PATH: timed out after 10 s, durability UNVERIFIED.

Unit tests: 1288/1288 pass (+14):

• timeout: 10 s default; a probe that never answers resolves at the deadline; a late answer replaces the verdict; health line formats;
• checkWritePath verdicts: ok, missing tables, connection refused → unreachable, auth failure → unreachable. Both unreachable cases fail on main, where they report supabase, ok;
• WARN lines: subsystem name, cause, stored OK / NOT stored on every line, unknown subsystem, no failures → no WARN.

No existing test encoded the old behaviour.

Checklist

• npm run test:unit passes (1288)
• New tests added
• No schema change; verified on a v1.8.0 store
• Docs: none describe health output

Breaking changes

None. health gains a first line and a write_path field; close WARN text changes.

🤖 Generated with Claude Code