feat: wikitool upstream merge/verify - code procedure for taking a stack update (4.5.0-beta.1, #30)

Files changed:
- AGENTS.md
- CHANGES.md
- VERSION
- instructions/gates.md
- instructions/private-instance.md
- tools/CONTRACT.md
- tools/README.md
- tools/chemenu/cli.py
- tools/chemenu/commands/dist_cmd.py
- tools/chemenu/commands/run_budget.py
- tools/chemenu/commands/upstream_cmd.py
- tools/chemenu/ownership.py
- tools/chemenu/tests/test_upstream_cmd.py

tools/chemenu/commands/dist_cmd.py

@@ -39,7 +39,7 @@ from typing import Callable, NamedTuple, Optional, Union
 
 import typer
 
-from chemenu import config, conventions, kb_collections, kb_state, version as version_mod
+from chemenu import config, conventions, kb_collections, kb_state, ownership, version as version_mod
 from chemenu.commands._util import fail, rel_path, success, today_iso
 
 app = typer.Typer(help="Build a distributable copy of the wiki machinery.")
@@ -132,8 +132,15 @@ INSTRUCTIONS_EXCLUDE_DIRS = {"dev"}
 RAW_SUBDIRS = ("articles", "documents", "notes", "assets")
 
 # Stage contracts that are not collections and carry no pages: copied as a
-# single file each, nothing else from their directory.
-CONTRACT_ONLY_STAGES = ("raw/CONTRACT.md", "reports/CONTRACT.md", "work/CONTRACT.md")
+# single file each, nothing else from their directory. `kb/` is excluded here
+# - it is a content stage too, but it has collections underneath it, so its
+# contract is handled by `build_plan` alongside them rather than as a bare
+# stage copy. Derived from `ownership.CONTENT_STAGES` rather than listed
+# again, so the set this loop copies and the set `upstream merge` restores
+# cannot name a different stage without one of them failing its own test.
+CONTRACT_ONLY_STAGES = tuple(
+    f"{stage}/CONTRACT.md" for stage in ownership.CONTENT_STAGES if stage != "kb"
+)
 
 # Single tracked files copied out of an otherwise-untouched, partially-ignored
 # directory. `.claude/` holds the harness's own session-tracing config
@@ -439,19 +446,20 @@ def build_plan(origin: Optional[Origin] = None) -> dict[str, PlannedFile]:
 # appears in INSTALL.md and version.py, so such a scan would either whitelist
 # the very string it is looking for or cry wolf on every export.
 #
-# `COLLECTION.md` and `CONVENTIONS.md` are deliberately *not* on the allowed
-# list any more. Both bind, and both are the instance's to write, so they cross
-# the boundary as `.template` and are adopted by a rename - a plan carrying the
+# `COLLECTION.md` and `CONVENTIONS.md` are deliberately *not* allowed through
+# any more. Both bind, and both are the instance's to write, so they cross the
+# boundary as `.template` and are adopted by a rename - a plan carrying the
 # filled name would hand a new instance this one's authoring conventions as
 # though they were the stack's.
+#
+# What counts as machinery under kb/ or raw/ is no longer a second list here:
+# it is `ownership.is_stack_owned`, the same predicate `upstream merge` and
+# `upstream verify` restore/check against. Only the export-only stubs
+# (`ownership.EXPORT_STUB_NAMES`) are allowed here without also being
+# stack-owned - a merge keeps the *local* copy of those, while export writes a
+# fresh one regardless of either side, so the two callers genuinely disagree
+# about them and each keeps its own allowance for that one case.
 _CONTENT_PREFIXES = ("kb/", "raw/")
-_CONTENT_ALLOWED_NAMES = (
-    "CONTRACT.md",
-    f"{kb_collections.CONTRACT_NAME}.template",
-    conventions.CONVENTIONS_TEMPLATE,
-    "log.md",
-    ".gitkeep",
-)
 _INSTANCE_OWNED_KB_FILES = (kb_collections.CONTRACT_NAME, conventions.CONVENTIONS_FILENAME)
 
 
@@ -473,7 +481,11 @@ def find_leaks(plan: dict[str, PlannedFile]) -> list[str]:
             leaks.append(f"{relative} (this instance's page type-spec; ship the .template)")
         elif relative.startswith("instructions/dev/"):
             leaks.append(f"{relative} (stack-development only)")
-        elif relative.startswith(_CONTENT_PREFIXES) and name not in _CONTENT_ALLOWED_NAMES:
+        elif (
+            relative.startswith(_CONTENT_PREFIXES)
+            and not ownership.is_stack_owned(relative)
+            and not ownership.is_export_stub(name)
+        ):
             leaks.append(f"{relative} (wiki content, not machinery)")
     return leaks