fix: resolve command references per integration type (dot vs hyphen) (#2354)

* fix: resolve command references per integration type (dot vs hyphen)

Replace hardcoded /speckit.<cmd> references in templates with
__SPECKIT_COMMAND_<NAME>__ placeholders that are resolved at
setup time based on the integration type:

- Markdown/TOML/YAML agents: separator='.' → /speckit.plan
- Skills agents: separator='-' → /speckit-plan

Changes:
- Add resolve_command_refs() static method to IntegrationBase
- Add invoke_separator class attribute (.  for base, - for skills)
- Wire into process_template() as step 8
- Update _install_shared_infra() to process page templates
- Replace /speckit.* in 5 command templates and 3 page templates
- Add unit tests for resolve_command_refs (positive + negative)
- Add integration tests verifying on-disk content for all agents
- Add end-to-end CLI tests for Claude (skills) and Copilot (markdown)

Fixes #2347

* review: use effective_invoke_separator() for Copilot skills mode

Address PR review feedback: instead of bleeding _skills_mode
knowledge into the CLI layer, add effective_invoke_separator()
method to IntegrationBase that accepts parsed_options.

CopilotIntegration overrides it to return "-" when skills
mode is requested. The CLI layer simply asks the integration
for its separator — no hasattr or _skills_mode coupling.

Also adds tests for the new method on both base and Copilot,
plus an end-to-end test for 'specify init --integration copilot
--integration-options --skills' verifying page templates get
hyphen refs.

* fix: build_command_invocation preserves full suffix for extension commands

Previously rsplit('.', 1)[-1] on 'speckit.git.commit' yielded
just 'commit', producing /speckit.commit instead of
/speckit.git.commit (or /speckit-git-commit for skills).

Fix: strip only the 'speckit.' prefix when present, then join
remaining segments with the appropriate separator.

Updated in IntegrationBase, SkillsIntegration, and
CopilotIntegration. Added tests for extension commands in
build_command_invocation across all three.

* fix: Copilot dispatch_command() preserves full extension command suffix

dispatch_command() had the same rsplit('.', 1)[-1] bug as
build_command_invocation() — speckit.git.commit would dispatch
as /speckit-commit instead of /speckit-git-commit in skills
mode, or --agent speckit.commit instead of speckit.git.commit
in default mode.

src/specify_cli/integrations/base.py

@@ -84,6 +84,9 @@ class IntegrationBase(ABC):
     context_file: str | None = None
     """Relative path to the agent context file (e.g. ``CLAUDE.md``)."""
 
+    invoke_separator: str = "."
+    """Separator used in slash-command invocations (``"."`` → ``/speckit.plan``)."""
+
     # -- Markers for managed context section ------------------------------
 
     CONTEXT_MARKER_START = "<!-- SPECKIT START -->"
@@ -96,6 +99,18 @@ class IntegrationBase(ABC):
         """Return options this integration accepts. Default: none."""
         return []
 
+    def effective_invoke_separator(
+        self, parsed_options: dict[str, Any] | None = None
+    ) -> str:
+        """Return the invoke separator for the given options.
+
+        Subclasses whose separator depends on runtime options (e.g.
+        Copilot in ``--skills`` mode) should override this method.
+        The default implementation ignores *parsed_options* and returns
+        the class-level ``invoke_separator``.
+        """
+        return self.invoke_separator
+
     def build_exec_args(
         self,
         prompt: str,
@@ -122,11 +137,12 @@ class IntegrationBase(ABC):
         agents or ``"/speckit-specify my-feature"`` for skills agents.
 
         *command_name* may be a full dotted name like
-        ``"speckit.specify"`` or a bare stem like ``"specify"``.
+        ``"speckit.specify"``, an extension command like
+        ``"speckit.git.commit"``, or a bare stem like ``"specify"``.
         """
         stem = command_name
-        if "." in stem:
-            stem = stem.rsplit(".", 1)[-1]
+        if stem.startswith("speckit."):
+            stem = stem[len("speckit."):]
 
         invocation = f"/speckit.{stem}"
         if args:
@@ -597,6 +613,24 @@ class IntegrationBase(ABC):
 
         return True
 
+    @staticmethod
+    def resolve_command_refs(content: str, separator: str = ".") -> str:
+        """Replace ``__SPECKIT_COMMAND_<NAME>__`` placeholders with invocations.
+
+        Each placeholder encodes a command name in upper-case with
+        underscores (e.g. ``__SPECKIT_COMMAND_PLAN__``,
+        ``__SPECKIT_COMMAND_GIT_COMMIT__``).  The replacement uses
+        *separator* to join the segments:
+
+        * ``separator="."`` → ``/speckit.plan``, ``/speckit.git.commit``
+        * ``separator="-"`` → ``/speckit-plan``, ``/speckit-git-commit``
+        """
+        return re.sub(
+            r"__SPECKIT_COMMAND_([A-Z][A-Z0-9_]*)__",
+            lambda m: "/speckit" + separator + m.group(1).lower().replace("_", separator),
+            content,
+        )
+
     @staticmethod
     def process_template(
         content: str,
@@ -604,6 +638,7 @@ class IntegrationBase(ABC):
         script_type: str,
         arg_placeholder: str = "$ARGUMENTS",
         context_file: str = "",
+        invoke_separator: str = ".",
     ) -> str:
         """Process a raw command template into agent-ready content.
 
@@ -615,6 +650,7 @@ class IntegrationBase(ABC):
         5. Replace ``__AGENT__`` with *agent_name*
         6. Replace ``__CONTEXT_FILE__`` with *context_file*
         7. Rewrite paths: ``scripts/`` → ``.specify/scripts/`` etc.
+        8. Replace ``__SPECKIT_COMMAND_<NAME>__`` with invocation strings
         """
         # 1. Extract script command from frontmatter
         script_command = ""
@@ -684,6 +720,9 @@ class IntegrationBase(ABC):
 
         content = CommandRegistrar.rewrite_project_relative_paths(content)
 
+        # 8. Replace __SPECKIT_COMMAND_<NAME>__ with invocation strings
+        content = IntegrationBase.resolve_command_refs(content, invoke_separator)
+
         return content
 
     def setup(
@@ -1274,6 +1313,8 @@ class SkillsIntegration(IntegrationBase):
     ``speckit-<name>/SKILL.md`` file with skills-oriented frontmatter.
     """
 
+    invoke_separator = "-"
+
     def build_exec_args(
         self,
         prompt: str,
@@ -1311,10 +1352,10 @@ class SkillsIntegration(IntegrationBase):
     def build_command_invocation(self, command_name: str, args: str = "") -> str:
         """Skills use ``/speckit-<stem>`` (hyphenated directory name)."""
         stem = command_name
-        if "." in stem:
-            stem = stem.rsplit(".", 1)[-1]
+        if stem.startswith("speckit."):
+            stem = stem[len("speckit."):]
 
-        invocation = f"/speckit-{stem}"
+        invocation = "/speckit-" + stem.replace(".", "-")
         if args:
             invocation = f"{invocation} {args}"
         return invocation
@@ -1395,6 +1436,7 @@ class SkillsIntegration(IntegrationBase):
             processed_body = self.process_template(
                 raw, self.key, script_type, arg_placeholder,
                 context_file=self.context_file or "",
+                invoke_separator=self.invoke_separator,
             )
             # Strip the processed frontmatter — we rebuild it for skills.
             # Preserve leading whitespace in the body to match release ZIP