feat: add shell auto-completion support

[rm-hull]

Added --bash and --zsh flags to generate completion scripts for Bash and Zsh, and updated documentation with installation instructions.

[github-actions]

	Tests	Passed ✅	Skipped	Failed
JUnit Test Report	63 ran	63 passed	0 skipped	0 failed

Test	Result
JUnit Test Report
com/rm-hull/git-commit-summary/internal/config.TestLoad/Defaults	✅ passed
com/rm-hull/git-commit-summary/internal/config.TestLoad/WithEnvironmentVariables	✅ passed
com/rm-hull/git-commit-summary/internal/config.TestLoad	✅ passed
com/rm-hull/git-commit-summary/internal/config.Test_updateProperties/handle_empty_quoted_strings	✅ passed
com/rm-hull/git-commit-summary/internal/config.Test_updateProperties/empty_file,_add_new_properties	✅ passed
com/rm-hull/git-commit-summary/internal/config.Test_updateProperties/existing_file,_update_properties	✅ passed
com/rm-hull/git-commit-summary/internal/config.Test_updateProperties/doesnt_overwrite_values_if_new_value_is_the_same	✅ passed
com/rm-hull/git-commit-summary/internal/config.Test_updateProperties/existing_file,_add_new_and_update_existing	✅ passed
com/rm-hull/git-commit-summary/internal/config.Test_updateProperties/preserve_comments_and_other_lines	✅ passed
com/rm-hull/git-commit-summary/internal/config.Test_updateProperties/handle_mixed_quoting_styles	✅ passed
com/rm-hull/git-commit-summary/internal/config.Test_updateProperties/empty_props,_no_changes	✅ passed
com/rm-hull/git-commit-summary/internal/config.Test_updateProperties/properties_with_special_characters	✅ passed
com/rm-hull/git-commit-summary/internal/config.Test_updateProperties	✅ passed
com/rm-hull/git-commit-summary/internal/git.TestClient_prepareCommitMessage/Single_line_message_with_skipCI	✅ passed
com/rm-hull/git-commit-summary/internal/git.TestClient_prepareCommitMessage/Multi-line_message_with_skipCI	✅ passed
com/rm-hull/git-commit-summary/internal/git.TestClient_prepareCommitMessage/Single_line_message_without_skipCI	✅ passed
com/rm-hull/git-commit-summary/internal/git.TestClient_prepareCommitMessage/Multi-line_message_without_skipCI	✅ passed
com/rm-hull/git-commit-summary/internal/git.TestClient_prepareCommitMessage/Empty_message_with_skipCI	✅ passed
com/rm-hull/git-commit-summary/internal/git.TestClient_prepareCommitMessage	✅ passed
com/rm-hull/git-commit-summary/internal/llm_provider.TestNewProvider/GoogleProvider	✅ passed
com/rm-hull/git-commit-summary/internal/llm_provider.TestNewProvider/OpenAIProvider	✅ passed
com/rm-hull/git-commit-summary/internal/llm_provider.TestNewProvider/UnknownProvider	✅ passed
com/rm-hull/git-commit-summary/internal/llm_provider.TestNewProvider	✅ passed
com/rm-hull/git-commit-summary/internal/ui.TestHistory/NewHistory	✅ passed
com/rm-hull/git-commit-summary/internal/ui.TestHistory/Add_and_Value	✅ passed
com/rm-hull/git-commit-summary/internal/ui.TestHistory/Undo	✅ passed
com/rm-hull/git-commit-summary/internal/ui.TestHistory/Redo	✅ passed
com/rm-hull/git-commit-summary/internal/ui.TestHistory/Undo_at_beginning	✅ passed
com/rm-hull/git-commit-summary/internal/ui.TestHistory/Redo_at_end	✅ passed
com/rm-hull/git-commit-summary/internal/ui.TestHistory/Add_truncates_future_history	✅ passed
com/rm-hull/git-commit-summary/internal/ui.TestHistory/Multiple_Undos_and_Redos	✅ passed
com/rm-hull/git-commit-summary/internal/ui.TestHistory	✅ passed
com/rm-hull/git-commit-summary/internal/ui.TestModel_Update/tea.KeyMsg_-_CtrlC_in_showSpinner_state	✅ passed
com/rm-hull/git-commit-summary/internal/ui.TestModel_Update/tea.KeyMsg_-_CtrlC_in_other_states	✅ passed
com/rm-hull/git-commit-summary/internal/ui.TestModel_Update/gitCheckMsg_-_empty_(no_staged_changes)	✅ passed
com/rm-hull/git-commit-summary/internal/ui.TestModel_Update/gitCheckMsg_-_non-empty_(staged_changes)	✅ passed
com/rm-hull/git-commit-summary/internal/ui.TestModel_Update/gitDiffMsg_with_hint	✅ passed
com/rm-hull/git-commit-summary/internal/ui.TestModel_Update/llmResultMsg_-_with_user_message	✅ passed
com/rm-hull/git-commit-summary/internal/ui.TestModel_Update/llmResultMsg_-_without_user_message	✅ passed
com/rm-hull/git-commit-summary/internal/ui.TestModel_Update/commitMsg	✅ passed
com/rm-hull/git-commit-summary/internal/ui.TestModel_Update/regenerateMsg_-_initializes_promptView_with_current_hint	✅ passed
com/rm-hull/git-commit-summary/internal/ui.TestModel_Update/userResponseMsg_-_updates_m.hint	✅ passed
com/rm-hull/git-commit-summary/internal/ui.TestModel_Update/cancelRegenPromptMsg_-_re-enables_help_text	✅ passed
com/rm-hull/git-commit-summary/internal/ui.TestModel_Update/errMsg	✅ passed
com/rm-hull/git-commit-summary/internal/ui.TestModel_Update/abortMsg	✅ passed
com/rm-hull/git-commit-summary/internal/ui.TestModel_Update/spinner.Update_for_showSpinner_state	✅ passed
com/rm-hull/git-commit-summary/internal/ui.TestModel_Update/commitView.Update_for_showCommitView_state	✅ passed
com/rm-hull/git-commit-summary/internal/ui.TestModel_Update/promptView.Update_for_showRegeneratePrompt_state	✅ passed
com/rm-hull/git-commit-summary/internal/ui.TestModel_Update/llmResultMsg_-_YOLO_mode	✅ passed
com/rm-hull/git-commit-summary/internal/ui.TestModel_Update/llmResultMsg_-_YOLO_mode_-_empty_summary	✅ passed
com/rm-hull/git-commit-summary/internal/ui.TestModel_Update/gitDiffMsg_-_includes_recent_commits_in_prompt	✅ passed
com/rm-hull/git-commit-summary/internal/ui.TestModel_Update	✅ passed
com/rm-hull/git-commit-summary/internal/ui.TestTrimTrailingSpaces/no_trailing_spaces	✅ passed
com/rm-hull/git-commit-summary/internal/ui.TestTrimTrailingSpaces/trailing_spaces_on_some_lines	✅ passed
com/rm-hull/git-commit-summary/internal/ui.TestTrimTrailingSpaces/tabs_and_carriage_returns	✅ passed
com/rm-hull/git-commit-summary/internal/ui.TestTrimTrailingSpaces/empty_string	✅ passed
com/rm-hull/git-commit-summary/internal/ui.TestTrimTrailingSpaces/single_line_with_space	✅ passed
com/rm-hull/git-commit-summary/internal/ui.TestTrimTrailingSpaces	✅ passed
com/rm-hull/git-commit-summary/internal/version.TestCheckLatestReturnsLatestWhenNewer	✅ passed
com/rm-hull/git-commit-summary/internal/version.TestCheckLatestReturnsEmptyWhenUpToDate	✅ passed
com/rm-hull/git-commit-summary/internal/version.TestCheckLatestReturnsEmptyForDevel	✅ passed
com/rm-hull/git-commit-summary/internal/version.TestCheckLatestWithRevSuffix	✅ passed
com/rm-hull/git-commit-summary/internal/version.TestCheckLatestWithRevSuffixAndUpToDate	✅ passed

• View JUnit Test Report

[gemini-code-assist]

Code Review

This pull request introduces shell auto-completion support for Bash and Zsh by adding --bash and --zsh flags, along with updating the README documentation. The review feedback suggests safely retrieving flag values using cmd.Flags().GetBool(...) to prevent potential nil pointer panics, handling errors from the completion generators, cleaning up unused flag pointer variables, and correcting the markdown syntax highlighting for the Zsh instructions in the README.

Important

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For more details on the timeline and next steps, please review the Help Documentation.

[coveralls]

Coverage Report for CI Build 28684480732

Coverage decreased (-0.3%) to 29.424%

Details

• Coverage decreased (-0.3%) from the base build.
• Patch coverage: 12 uncovered changes across 1 file (0 of 12 lines covered, 0.0%).
• No coverage regressions found.

Uncovered Changes

File	Changed	Covered	%
main.go	12	0	0.0%

Coverage Regressions

No coverage regressions found.

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Coverage Stats

Relevant Lines:	1424
Covered Lines:	419
Line Coverage:	29.42%
Coverage Strength:	0.32 hits per line

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💛 - Coveralls