Keep local config files out of the Docker build context (closes #211)

config.yaml and config.dev.yml are kept out of git because they can hold
the signing key, but .dockerignore did not leave them out, so a local
copy in the working tree reached the build context and, through
COPY . ., a build-stage layer. .dockerignore now leaves them out in
every directory. configs/config.example.yml is still sent.

Model: opus-5-5

.dockerignore

@@ -68,5 +68,5 @@
 /data
 
 # Local config files, kept out of git because they can hold the signing key.
-**/[cC][oO][nN][fF][iI][gG].[yY][aA][mM][lL]
+**/config.yaml
-**/[cC][oO][nN][fF][iI][gG].[dD][eE][vV].[yY][mM][lL]
+**/config.dev.yml

.gitignore

@@ -11,12 +11,6 @@ Thumbs.db
 .vscode/
 *.sublime-*
 
-# Agent scratch (worktrees of this repo, created and destroyed by
-# in-flight tooling). Unanchored: .gitignore patterns already match at
-# every depth, so no prefix is wanted here. This is not a .dockerignore
-# entry and must not be given a `**/` prefix on the way into one.
-.claude/
-
 # Environment / secrets
 .env
 .env.*

TODO.md

@@ -33,15 +33,10 @@ P2: security: per-IP rate limiting on the image routes
 
 - 2026-10-04 local config files stay out of the Docker build context (closes
   #211): `.dockerignore` now leaves out `config.yaml` and `config.dev.yml` in
-  every directory and in any letter case, the local config files `.gitignore`
+  every directory, the local config files `.gitignore` keeps out of git because
-  keeps out of git because they can hold the signing key.
+  they can hold the signing key. `configs/config.example.yml` is still sent.
-  `configs/config.example.yml` is still sent. `config.yml`, which Getting
+  `config.yml`, which Getting Started creates, is in neither file:
-  Started creates, is in neither file:
   https://git.eeqj.de/sneak/pixa/issues/212.
-- 2026-10-04 `.gitignore` ignores `.claude/` (closes #204): the entry and its
-  comment are copied from the canonical `.gitignore` in `sneak/prompts`,
-  unanchored so it matches at every depth. `.dockerignore` already has
-  `.claude`.
 - 2026-10-04 `.dockerignore` keeps secrets out at every depth (closes #205): the
   file is now the standard one from `sneak/prompts`, whose patterns match in
   every directory and, for environment files and private keys, in any letter