docs(ISSUE-WP-0006): Forgejo-only language and projection boundary

Prefer Forgejo as the self-hosted forge product. Keep Gitea only as the
Gitea-compatible API identifier (module backends/gitea, type string
gitea). FORGEJO_TOKEN is preferred; GITEA_* remains a deprecated alias.

INTENT/SCOPE quote ACT-ADR-005: issue-core is not the fleet ops claim
queue. Connector docs describe repo work record → hub index → optional
Forgejo projection, not activity-core → issue-core → harness.

Assistant: grok
Assistant-Session: 01a09dc6-3f0d-7c93-8b11-8e83c0623d49

ROADMAP.md

@@ -28,7 +28,7 @@ replacing workplans/tasks.
 
 ✅ **Complete:**
 - Core CRUD operations (100%)
-- Gitea backend (production-ready)
+- Forgejo backend (Gitea-compatible API; production-ready)
 - Local SQLite backend (fully functional)
 - CLI with JSON output
 - Python programmatic API
@@ -80,8 +80,8 @@ def detect_git_remote() -> Optional[Dict[str, str]]:
 
     Returns:
         {
-            'platform': 'gitea' | 'github' | 'gitlab',
-            'base_url': 'https://gitea.example.com',
+            'platform': 'forgejo' | 'github' | 'gitlab',
+            'base_url': 'https://forgejo.example.com',
             'owner': 'myorg',
             'repo': 'myproject'
         }
@@ -90,15 +90,15 @@ def detect_git_remote() -> Optional[Dict[str, str]]:
 def parse_remote_url(url: str) -> Optional[Dict[str, str]]:
     """
     Parse various git remote URL formats:
-    - https://gitea.example.com/owner/repo.git
-    - git@gitea.example.com:owner/repo.git
+    - https://forgejo.example.com/owner/repo.git
+    - git@forgejo.example.com:owner/repo.git
     - https://github.com/owner/repo
     """
 ```
 
 **Tests:** `tests/test_detection.py`
 - Test various URL formats (HTTPS, SSH, with/without .git)
-- Test platform detection (Gitea, GitHub, GitLab)
+- Test platform detection (Forgejo, GitHub, GitLab)
 - Test edge cases (subgroups, custom domains)
 
 **Effort:** 2-3 days
@@ -112,7 +112,8 @@ def parse_remote_url(url: str) -> Optional[Dict[str, str]]:
 def load_backend_from_env() -> Optional[Dict[str, Any]]:
     """
     Load backend config from environment variables:
-    - GITEA_URL, GITEA_TOKEN, GITEA_OWNER, GITEA_REPO
+    - FORGEJO_URL, FORGEJO_TOKEN, FORGEJO_OWNER, FORGEJO_REPO
+      (deprecated aliases: GITEA_URL, GITEA_TOKEN / GITEA_API_TOKEN, …)
     - GITHUB_TOKEN (with auto-detection)
     - GITLAB_URL, GITLAB_TOKEN
     """
@@ -149,10 +150,10 @@ issue config auto
 {
   "backend": {
     "type": "gitea",
-    "url": "https://gitea.example.com",
+    "url": "https://forgejo.example.com",
     "owner": "myorg",
     "repo": "myproject",
-    "token_source": "env:GITEA_TOKEN"  // or "file:/path/to/token"
+    "token_source": "env:FORGEJO_TOKEN"  // or "file:/path/to/token"; GITEA_* deprecated
   },
   "sync": {
     "enabled": true,
@@ -247,7 +248,7 @@ if issue backend show "$backend_name" &>/dev/null; then
         fi
 
         # Offer existing values as defaults
-        read -p "Gitea URL [$CURRENT_URL]: " url
+        read -p "Forgejo URL [$CURRENT_URL]: " url
         url="${url:-$CURRENT_URL}"
 
         read -p "Repository owner [$CURRENT_OWNER]: " owner
@@ -403,7 +404,7 @@ class LockManager:
 
 **Storage:** Store claims in issue metadata or separate tracking table.
 
-**For Gitea backend:**
+**For Forgejo backend:**
 ```json
 // In issue.sync_metadata
 {
@@ -788,7 +789,7 @@ def sync_with_strategy(
 
 ### Phase 1 Success
 - [ ] Agent can attach to any repo's tracker with zero manual config
-- [ ] Environment-only setup works: `GITEA_TOKEN=xxx issue list`
+- [ ] Environment-only setup works: `FORGEJO_TOKEN=xxx issue list`
 - [ ] Auto-detection accuracy: >95% for common platforms
 
 ### Phase 1.5 Success (mapping)