Replace REPO_POLICIES.md with the canonical copy from sneak/prompts (closes #196)

REPO_POLICIES.md is fetched unchanged from prompts/REPO_POLICIES.md on
sneak/prompts main. The new rules pixa's tree breaks are filed as
#202 through
#206 and
#208 and not fixed here. Its rule
that no build stage runs git describe is not followed, per
#166.

Model: opus-5-5

TODO.md

@@ -31,6 +31,21 @@ P2: security: per-IP rate limiting on the image routes
 
 # Completed Steps
 
+- 2026-10-04 `REPO_POLICIES.md` matches the canonical copy again (closes #196):
+  it is replaced, unchanged, by `prompts/REPO_POLICIES.md` from `sneak/prompts`
+  `main`. The rules it adds that pixa's tree breaks are filed:
+  https://git.eeqj.de/sneak/pixa/issues/202 (lint and tests as `Dockerfile`
+  phases built with `--no-cache`), https://git.eeqj.de/sneak/pixa/issues/203
+  (the workflow's `script/docker-smoke` step),
+  https://git.eeqj.de/sneak/pixa/issues/204 (`.claude/` in `.gitignore`),
+  https://git.eeqj.de/sneak/pixa/issues/205 (`.dockerignore` patterns at every
+  depth), https://git.eeqj.de/sneak/pixa/issues/206 (a thin
+  `cmd/pixad/main.go`) and https://git.eeqj.de/sneak/pixa/issues/208
+  (`fetch-depth: 0` on the CI checkout, so the build sees the tags). Its rule
+  that no build stage runs `git describe` is not followed: pixa takes the
+  version from the `.git` in the build context, per
+  https://git.eeqj.de/sneak/pixa/issues/166, as the copy on `sneak/prompts`
+  `next` already says.
 - 2026-10-04 an integration test of the image proxy flow (closes #80):
   `TestImageProxyFlow` in `internal/server` starts the database, handlers and
   middleware from the constructors `pixad` uses, with a fresh state directory,