fix: authenticate Woodpecker CI clone step when Forgejo requires sign-in (#353)

Forgejo with REQUIRE_SIGN_IN blocks anonymous git clones (exit code 128).
Add WOODPECKER_ENVIRONMENT to inject FORGE_TOKEN into all pipeline steps,
and override the default clone step in ci.yml to use an authenticated URL
built from FORGE_TOKEN — bypassing the expired stored OAuth token.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

lib/generators.sh

@@ -79,6 +79,7 @@ services:
       WOODPECKER_AGENT_SECRET: ${WOODPECKER_AGENT_SECRET:-}
       WOODPECKER_DATABASE_DRIVER: sqlite3
       WOODPECKER_DATABASE_DATASOURCE: /var/lib/woodpecker/woodpecker.sqlite
+      WOODPECKER_ENVIRONMENT: "FORGE_TOKEN:${FORGE_TOKEN}"
     depends_on:
       - forgejo
     networks: