fix(taiga-auto-sync): match real Taiga MCP tool names and drop impossible owner/sprint checks

The write-guard's matcher regex never matched the actual tool names
(createUserStory/createTask/createIssue, not user_story_create etc.), so
the metadata guard has never actually fired. It also checked for
assigned_to/milestone fields that don't exist on any create tool's
schema, which would have denied every create once the matcher was fixed.
Guard now validates only the tag contract (area/source/target), covers
the batch-create tools per item, and SKILL.md documents the real
follow-up calls (assignIssue/assignUserStoryToSprint/addIssueToSprint)
needed to set owner and sprint after creation.

plugins/taiga-auto-sync/hooks/taiga-write-guard.py

@@ -1,5 +1,13 @@
 #!/usr/bin/env python3
-"""Reject Taiga item creation without the active-item metadata contract."""
+"""Reject Taiga item creation that is missing the required tag contract.
+
+Only checks tags. Owner and sprint are not creation-time fields on the
+Taiga MCP server's create tools (createUserStory/createTask/createIssue and
+their batch variants) -- they are set afterwards via assignIssue,
+assignUserStoryToSprint, or addIssueToSprint. Tasks have no assignee/sprint
+tool at all, so their owner and sprint are tracked through the parent
+User Story instead.
+"""
 import json
 import sys
 
@@ -8,15 +16,14 @@ AREAS = {
     "access", "automation", "support", "vendor",
 }
 
+# Batch-create tools nest each item's tags under one of these list keys
+# instead of exposing a top-level "tags" array.
+BATCH_LIST_KEYS = ("userStories", "tasks", "issues")
 
-def missing_fields(payload):
-    item = payload.get("tool_input", {})
-    tags = set(item.get("tags") or [])
+
+def missing_tag_fields(tags):
+    tags = set(tags or [])
     missing = []
-    if not item.get("assigned_to"):
-        missing.append("owner")
-    if not item.get("milestone"):
-        missing.append("current sprint")
     if not tags.intersection(AREAS):
         missing.append("area tag")
     if not any(tag.startswith("source:") for tag in tags):
@@ -26,6 +33,21 @@ def missing_fields(payload):
     return missing
 
 
+def missing_fields(payload):
+    item = payload.get("tool_input", {})
+    for key in BATCH_LIST_KEYS:
+        entries = item.get(key)
+        if isinstance(entries, list):
+            problems = []
+            for index, entry in enumerate(entries):
+                missing = missing_tag_fields(entry.get("tags"))
+                if missing:
+                    label = entry.get("subject") or f"item {index}"
+                    problems.append(f"{label!r}: missing " + ", ".join(missing))
+            return problems
+    return missing_tag_fields(item.get("tags"))
+
+
 def result(payload):
     missing = missing_fields(payload)
     if not missing:
@@ -35,8 +57,13 @@ def result(payload):
             "hookEventName": "PreToolUse",
             "permissionDecision": "deny",
             "permissionDecisionReason": (
-                "Taiga item creation requires " + ", ".join(missing) +
-                ". Resolve or create the current WIB sprint first."
+                "Taiga item is missing required tags: " + "; ".join(missing) + ". "
+                "Apply one area tag, one source:<agent> tag, and one "
+                "repo:<name>/system:<name> tag. Owner and sprint are not "
+                "creation-time fields here -- set them right after creation "
+                "with assignIssue / assignUserStoryToSprint / addIssueToSprint "
+                "(Tasks have no assignee/sprint tool; track Task ownership and "
+                "sprint through the parent User Story)."
             ),
         }
     }
@@ -44,9 +71,20 @@ def result(payload):
 
 def main():
     if sys.argv[1:] == ["--self-check"]:
-        assert result({"tool_input": {"assigned_to": 1, "milestone": 1,
-                                        "tags": ["infra", "source:codex", "repo:brain"]}}) is None
-        assert result({"tool_input": {"tags": []}})
+        ok_tags = ["infra", "source:codex", "repo:brain"]
+
+        assert result({"tool_input": {"tags": ok_tags}}) is None
+        assert result({"tool_input": {"tags": []}}) is not None
+
+        ok_batch = {"tool_input": {"issues": [{"subject": "a", "tags": ok_tags}]}}
+        assert result(ok_batch) is None
+
+        bad_batch = {"tool_input": {"issues": [
+            {"subject": "a", "tags": ok_tags},
+            {"subject": "b", "tags": []},
+        ]}}
+        assert result(bad_batch) is not None
+
         print("self-check: ok")
         return
     output = result(json.load(sys.stdin))