config: track public cc-ci runtime environment

Route deepseek-v4-flash through the opencode zen subscription endpoint
(opencode/deepseek-v4-flash) instead of tinfoil pay-per-use. The zen
subscription is already paid for; flash consumes the balance far more
slowly than glm-5.2 did (flash cost ~$0.0000002/tok vs glm's higher rate),
so a full weekly run is much less likely to exhaust the balance — and
the operator has reset it.

Completes the fleet-wide move: upgrader parent (LOOP_MODEL) + report
(REPORT_MODEL) in upgrader.env, and this PR sets the subagents. Supervisor
stays on opencode-go/glm-5.2.

Verified: zen endpoint serves deepseek-v4-flash (HTTP 200, 1.2s).

.env.public

@@ -0,0 +1,7 @@
+# Non-sensitive runtime configuration shared by the cc-ci orchestrator and agents.
+#
+# Keep credentials, tokens, and keys in /srv/cc-ci/.testenv.  The orchestrator
+# loads this file first via cc-ci-plan/load-env.sh.
+GITEA_USERNAME=autonomic-bot
+TINFOIL_MODEL=deepseek-v4-pro
+TINFOIL_BASE_URL=https://inference.tinfoil.sh/v1

docs/public-environment.md

@@ -0,0 +1,15 @@
+# Public runtime environment
+
+`.env.public` contains non-sensitive configuration that the cc-ci orchestrator
+and its agent sessions need at runtime. It is intentionally tracked so it can
+be inspected and reproduced with the rest of the CI configuration.
+
+Load it together with the local secret file by sourcing
+`/srv/cc-ci/cc-ci-plan/load-env.sh`. The helper reads `.env.public` first and
+then `/srv/cc-ci/.testenv`; credentials, tokens, and keys belong only in the
+latter file.
+
+Do not put a value in `.env.public` merely because it is convenient. If it
+would grant access or require rotation, it is a secret and belongs in
+`.testenv`. Public service endpoints, model names, and account identifiers may
+be tracked here.

opencode.json

@@ -2,7 +2,7 @@
   "$schema": "https://opencode.ai/config.json",
   "agent": {
     "general": {
-      "model": "tinfoil/deepseek-v4-flash"
+      "model": "opencode/deepseek-v4-flash"
     }
   }
 }