docs: record font deployment and development write protection

docs/PRODUCTION.md

@@ -8,10 +8,10 @@ Docker starts at boot; containers use `restart: unless-stopped`.
 
 ## Release and configuration
 
-Current image: `minabot:20260907-c7aa5a1-2`, built on the Linux amd64 server from
-the local checkout based on `c7aa5a1` plus the Docker and trusted-proxy changes.
+Current image: `minabot:20260907-fonts-1`, built on the Linux amd64 server from
+commit `1721ee4`, including development write protection and bundled share fonts.
 Its immutable image ID is recorded by `docker image inspect`; source is retained
-under `/opt/minabot/releases/20260907-c7aa5a1-2`, with `source-v2.tar.gz` and build
+under `/opt/minabot/releases/20260907-fonts-1`, with `source.tar.gz` and build
 logs in `/opt/minabot`. Bun 1.3.14 and Caddy images are pinned by digest.
 
 `/opt/minabot/.env` selects release images. `/opt/minabot/.env.production` contains
@@ -75,7 +75,7 @@ a suitable rollback target for working production sign-in.
 
 ## Verified September 7, 2026
 
-- Typecheck, build, 195 tests, and production HTTP smoke tests passed.
+- Typecheck, build, 197 tests, and production HTTP smoke tests passed.
 - The Linux runtime passed migrations, native 1920×1080 PNG rendering, and
   persistence across a process restart using a disposable database.
 - Public HTTPS health returns `{"status":"ok"}`; HTTP redirects to HTTPS.
@@ -88,3 +88,10 @@ a suitable rollback target for working production sign-in.
 
 Live Discord test posts/DMs were not sent. Existing configured workers continue
 their normal production behavior.
+
+## Share fonts
+
+Instrument Serif and Noto Sans (400/500/600) are bundled for both browser and native
+canvas share renderers. Mac/Linux fixture text metrics match exactly; pixel-channel
+differences are at most 2/255 from native rasterization. Missing native font files
+fail startup. Renderer version 3 refreshes existing live cards with the new fonts.