fix: Raise proper error message for invalid format functions

[Ruari-Phipps]

Summary

Fixes two related issues: untyped or unsupported function parameters now raise a clear ValueError instead of crashing with AttributeError, and merge-conflicted files are correctly excluded from modified_files in project_status and handled without crashing in get_diffs. Also surfaces all CLI errors as structured JSON when --json is set.

Motivation

In v0.6.x, functions with untyped parameters (e.g. def f(conv, booking_ref)) caused _extract_decorators to crash with AttributeError: 'NoneType' has no attribute 'id'. Separately, files with merge conflicts were being passed to read_local_resource, which would now raise rather than silently fail. Both issues needed to be fixed together for poly status and poly diff to be reliable after a branch pull with conflicts.

Closes #

Changes

• _extract_decorators: guard arg.annotation access before reading .id; raise ValueError with a distinct message for missing vs unsupported type annotations; remove the try/except SyntaxError wrapper so errors propagate to the user
• resource.py: rename get_status → is_modified, removing merge conflict detection from the resource itself
• project_status: check for merge conflicts on raw file content before calling read_local_resource; conflicted files now appear only in files_with_conflicts, not also in modified_files
• get_diffs: same conflict-before-parse pattern; shows diff of conflict markers vs original; fix type(resource_type) key bug and missing second arg to get_diff
• cli.py: wrap the command dispatch in try/except; when --json is set, errors are returned as {"success": false, "error": "...", "traceback": "..."} instead of raising
• src/poly/docs/functions.md: note that all parameters must have a supported type annotation

Test strategy

• Added/updated unit tests
• Manual CLI testing (poly <command>)
• Tested against a live Agent Studio project
• N/A (docs, config, or trivial change)

Checklist

• ruff check . and ruff format --check . pass
• pytest passes
• No breaking changes to the poly CLI interface (or migration path documented)
• Commit messages follow conventional commits

Screenshots / Logs

[Copilot]

Pull request overview

Improves ADK’s robustness when parsing function decorators and handling merge-conflicted files so poly status, poly diff, and --json error output behave predictably instead of crashing on edge cases.

Changes:

• Make _extract_decorators raise clear ValueErrors for missing/unsupported type annotations (instead of crashing).
• Exclude merge-conflicted files from modified_files and avoid parsing conflicted content in project_status / get_diffs.
• Emit structured JSON errors (with traceback) from the CLI when --json is set; update docs and tests accordingly.

Reviewed changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
src/poly/resources/function.py	Updates decorator extraction to validate annotations and raise ValueError on invalid formats.
src/poly/resources/resource.py	Renames status API to is_modified() and removes merge-conflict detection from the resource layer.
src/poly/project.py	Detects merge conflicts from raw file contents before parsing; adjusts status/diff behavior.
src/poly/cli.py	Wraps command dispatch to return structured JSON error payloads when --json is used.
src/poly/docs/functions.md	Documents that parameters must have supported type annotations.
src/poly/tests/resources_test.py	Adds unit tests covering new decorator-extraction error cases.
src/poly/tests/project_test.py	Updates merge-conflict status expectations (conflicts no longer count as modified).

[github-actions]

Coverage Report

Base (main)	PR	Change
71.5%	71.5%	+0.0% ✅

Changed file coverage

File	Coverage	Change
poly/cli.py	43.5%	-0.2% ⚠️
poly/project.py	66.6%	-0.1% ⚠️
poly/resources/pronunciation.py	78.1%	+6.2% ✅
poly/resources/resource.py	79.5%	-0.1% ⚠️
poly/resources/function.py	80.9%	-0.5% ⚠️

[bill-parker]

lgtm!