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

issue_core/backends/__init__.py

@@ -7,5 +7,5 @@ API regardless of the underlying issue tracking system.
 
 Available Backends:
 - local: SQLite-based local backend for offline use
-- gitea: Gitea API backend for GitHub-compatible systems
+- gitea: Forgejo backend (Gitea-compatible API)
 """

issue_core/backends/gitea/__init__.py

@@ -1,12 +1,11 @@
 """
-Gitea Backend
+Forgejo backend (Gitea-compatible API).
 
-A backend implementation for Gitea issue tracking systems.
-This backend provides integration with Gitea API for remote issue management.
+Talks to the self-hosted Forgejo HTTP API. Gitea is not a second supported
+product. The backend type string remains `gitea`.
 
 Features:
-- Full Gitea API integration
-- GitHub-compatible operations
+- Full Forgejo / Gitea-compatible API integration
 - Remote synchronization
 - Authentication support
 - Rate limiting compliance

issue_core/backends/gitea/backend.py

@@ -1,8 +1,9 @@
 """
-Gitea Backend Implementation
+Forgejo backend (Gitea-compatible API).
 
-Provides integration with Gitea API for remote issue tracking.
-This backend adapts the Gitea API to our unified issue model.
+Talks to the self-hosted Forgejo HTTP API, which is Gitea-compatible.
+Gitea is not a second supported product. The backend type string remains
+`gitea` for compatibility.
 """
 
 import requests
@@ -16,7 +17,7 @@ from ...core.models import Issue, Label, User, Milestone, Comment, IssueState, P
 
 
 class GiteaAPIError(Exception):
-    """Gitea API specific errors."""
+    """Forgejo (Gitea-compatible API) errors."""
     pass
 
 
@@ -26,7 +27,7 @@ class GiteaRateLimitError(GiteaAPIError):
 
 
 class GiteaBackend(RemoteBackend, SyncableBackend):
-    """Gitea API backend for remote issue tracking."""
+    """Forgejo backend using the Gitea-compatible HTTP API."""
 
     def __init__(self):
         self.base_url: Optional[str] = None
@@ -44,7 +45,7 @@ class GiteaBackend(RemoteBackend, SyncableBackend):
             supports_webhooks=True,
             supports_real_time=False,
             max_labels_per_issue=None,
-            max_assignees_per_issue=10  # Gitea typical limit
+            max_assignees_per_issue=10  # Forgejo / Gitea-compatible typical limit
         )
 
     @property
@@ -56,7 +57,7 @@ class GiteaBackend(RemoteBackend, SyncableBackend):
         return self._capabilities
 
     def connect(self, config: Dict[str, Any]) -> None:
-        """Connect to Gitea API."""
+        """Connect to Forgejo (Gitea-compatible API)."""
         self.base_url = config['base_url'].rstrip('/')
         self.token = config['token']
         self.owner = config['owner']
@@ -71,10 +72,10 @@ class GiteaBackend(RemoteBackend, SyncableBackend):
 
         # Test connection
         if not self.test_connection():
-            raise GiteaAPIError("Failed to connect to Gitea API")
+            raise GiteaAPIError("Failed to connect to Forgejo (Gitea-compatible API)")
 
     def disconnect(self) -> None:
-        """Disconnect from Gitea API."""
+        """Disconnect from Forgejo."""
         self.session.close()
         self.base_url = None
         self.token = None
@@ -195,20 +196,20 @@ class GiteaBackend(RemoteBackend, SyncableBackend):
         if issue.milestone:
             data['milestone'] = int(issue.milestone.backend_id) if issue.milestone.backend_id else None
 
-        # Gitea expects numeric label IDs on issue create/update. Name-only
-        # labels are preserved in issue-core metadata but omitted from the API
-        # payload until a label-resolution step exists.
-        label_ids = []
-        for label in issue.labels:
-            if not label.backend_id:
-                continue
-            try:
-                label_ids.append(int(label.backend_id))
-            except (TypeError, ValueError):
-                continue
-        if label_ids:
-            data['labels'] = label_ids
-
+        # Gitea expects numeric label IDs on issue create/update. Name-only
+        # labels are preserved in issue-core metadata but omitted from the API
+        # payload until a label-resolution step exists.
+        label_ids = []
+        for label in issue.labels:
+            if not label.backend_id:
+                continue
+            try:
+                label_ids.append(int(label.backend_id))
+            except (TypeError, ValueError):
+                continue
+        if label_ids:
+            data['labels'] = label_ids
+
         return data
 
     # Issue CRUD Operations