chore: Bump version to 0.1.15

feat: Allow GOOGLE_MODEL env var to change the default model

feat: Update to gemini-2.0-flash-001 model and bump version.

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docs: Update README with flag descriptions and usage

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feat: Update version and improve command-line argument handling

feat: Bump version to 0.1.10 and remove test file.

feat: Improve push feedback and handle no file selection error

feat: Add push to github functionality and remove summarize command

package.json: Updates version to 0.1.8; src/commands/help.ts: Adds summarize command to help; src/index.ts: Adds summarize command; src/lib/ai.ts: Adds SummarizeChanges function;

package.json: Update version to 0.1.5 and add repository URL;

package.json: Update version and add gitai bin; src/commands/generate.ts: Fix typo in variable declaration; src/index.ts: Add version command.

package.json: Bump version to 0.1.3

src/commands/generate.ts: Add full git command option; src/index.ts: Add help command and handle no command case.