Remove trailing periods from tool title annotations

[timrogers]

Summary

• remove trailing periods from tool title annotations for affected tools
• keep tool descriptions unchanged
• regenerate tool snapshots and README docs to reflect the annotation text changes

Context

Titles ending with periods were inconsistent with most other tools and looked odd in agent UIs.

[Copilot]

Pull request overview

This pull request standardizes MCP tool title annotations by removing trailing periods for the affected tools, keeping tool descriptions intact, and regenerating the derived artifacts (toolsnaps + README docs) so the public/tooling-facing output matches.

Changes:

• Removed trailing periods from selected mcp.ToolAnnotations.Title strings.
• Regenerated tool schema snapshots under pkg/github/__toolsnaps__/ to reflect the updated titles.
• Updated autogenerated sections in README.md so rendered tool titles no longer end with periods.

Show a summary per file

File	Description
README.md	Updates generated tool listings to reflect title annotation punctuation changes.
pkg/github/pullrequests.go	Removes trailing period from pull_request_review_write tool title annotation.
pkg/github/labels.go	Removes trailing periods from label tool title annotations (get/list/write).
pkg/github/issues.go	Removes trailing period from issue_write tool title annotation.
pkg/github/toolsnaps/pull_request_review_write.snap	Updates snapshot title string to match tool title annotation.
pkg/github/toolsnaps/list_label.snap	Updates snapshot title string to match tool title annotation.
pkg/github/toolsnaps/label_write.snap	Updates snapshot title string to match tool title annotation.
pkg/github/toolsnaps/issue_write.snap	Updates snapshot title string to match tool title annotation.
pkg/github/toolsnaps/get_label.snap	Updates snapshot title string to match tool title annotation.

Copilot's findings

• Files reviewed: 9/9 changed files
• Comments generated: 1