Feature/spec kit add pi coding agent pullrequest (#1853)

* feat(ai): add native support for Pi coding agent by pi+gpt 5.4

* docs(pi): document MCP limitations for Pi agent

* fix: unitended kimi agent mention added to update-agent-context.ps1

* fix: address reviewer feedback

* Apply suggestions from code review

Changes in AGENTS.md weren't part of my PR, but the Copilot feedback seems to be correct is correct. I've doublechecked it with contents of test_agent_config_consistency.py and create-release-packages scripts

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

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Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

src/specify_cli/agents.py

@@ -106,6 +106,12 @@ class CommandRegistrar:
             "args": "$ARGUMENTS",
             "extension": ".md"
         },
+        "pi": {
+            "dir": ".pi/prompts",
+            "format": "markdown",
+            "args": "$ARGUMENTS",
+            "extension": ".md"
+        },
         "amp": {
             "dir": ".agents/commands",
             "format": "markdown",