Share skills hook note post-processing (#2679)

* fix(integrations): share skills hook note post-processing

* fix(integrations): tighten skill post-processing

Apply skill content post-processing before the initial write, use an exact hook-note sentinel for idempotence, and route Copilot skill post-processing through the shared helper before adding mode frontmatter.

* Make hook note injection per instruction

* Deduplicate Codex hook note processing

---------

Co-authored-by: Puneet Dixit <236133619+puneetdixit200@users.noreply.github.com>
Co-authored-by: Puneet Dixit <puneetdixit200@users.noreply.github.com>

src/specify_cli/integrations/codex/__init__.py

@@ -6,22 +6,7 @@ Commands are deprecated; ``--skills`` defaults to ``True``.
 
 from __future__ import annotations
 
-import re
-from pathlib import Path
-from typing import Any
-
 from ..base import IntegrationOption, SkillsIntegration
-from ..manifest import IntegrationManifest
-
-# Note injected into hook sections so Codex maps dot-notation command
-# names (from extensions.yml) to the hyphenated skill names it uses.
-# Without this, Codex emits ``/speckit.git.commit`` (which does not
-# resolve) instead of ``/speckit-git-commit``.
-_HOOK_COMMAND_NOTE = (
-    "- When constructing slash commands from hook command names, "
-    "replace dots (`.`) with hyphens (`-`). "
-    "For example, `speckit.git.commit` → `/speckit-git-commit`.\n"
-)
 
 
 class CodexIntegration(SkillsIntegration):
@@ -69,68 +54,3 @@ class CodexIntegration(SkillsIntegration):
                 help="Install as agent skills (default for Codex)",
             ),
         ]
-
-    @staticmethod
-    def _inject_hook_command_note(content: str) -> str:
-        """Insert a dot-to-hyphen note before each hook output instruction.
-
-        Targets the line ``- For each executable hook, output the following``
-        and inserts the note on the line before it, matching its indentation.
-        Skips if the note is already present.
-        """
-        if "replace dots" in content:
-            return content
-
-        def repl(m: re.Match[str]) -> str:
-            indent = m.group(1)
-            instruction = m.group(2)
-            # ``eol`` is empty when the regex matched via ``$`` because the
-            # instruction was the final line of a file with no trailing
-            # newline. Default to ``\n`` so the note never collapses onto
-            # the same line as the instruction.
-            eol = m.group(3) or "\n"
-            return (
-                indent
-                + _HOOK_COMMAND_NOTE.rstrip("\n")
-                + eol
-                + indent
-                + instruction
-                + eol
-            )
-
-        return re.sub(
-            r"(?m)^(\s*)(- For each executable hook, output the following[^\r\n]*)(\r\n|\n|$)",
-            repl,
-            content,
-        )
-
-    def post_process_skill_content(self, content: str) -> str:
-        """Inject the dot-to-hyphen hook command note."""
-        return self._inject_hook_command_note(content)
-
-    def setup(
-        self,
-        project_root: Path,
-        manifest: IntegrationManifest,
-        parsed_options: dict[str, Any] | None = None,
-        **opts: Any,
-    ) -> list[Path]:
-        """Install Codex skills, then inject the hook command note."""
-        created = super().setup(project_root, manifest, parsed_options, **opts)
-
-        skills_dir = self.skills_dest(project_root).resolve()
-        for path in created:
-            try:
-                path.resolve().relative_to(skills_dir)
-            except ValueError:
-                continue
-            if path.name != "SKILL.md":
-                continue
-
-            content = path.read_bytes().decode("utf-8")
-            updated = self.post_process_skill_content(content)
-            if updated != content:
-                path.write_bytes(updated.encode("utf-8"))
-                self.record_file_in_manifest(path, project_root, manifest)
-
-        return created