docs: add installation instructions for Gemini CLI

[lienweb]

Summary

Add detailed instructions for setting up and using the project with Gemini CLI. The new section guides users through cloning the repository, renaming files and folders, updating settings, and starting the coach using Gemini CLI.

[Copilot]

Pull request overview

Adds a third Quick Start pathway documenting how to set up and run the interview coach using Gemini CLI, alongside the existing Claude Code and OpenAI Codex options.

Changes:

• Add “Option 3: Gemini CLI” setup steps (clone, activate, rename config folder, update permissions, kickoff).
• Document Gemini-specific permission entries expected in the config.
• Link to Gemini CLI plans page for free/paid plan details.

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[Copilot]

The fenced code block for step 3 isn’t separated/indented under the numbered list item, which can break list formatting in GitHub/CommonMark. Add a blank line before the fence and indent the fenced block so it’s clearly nested under item 3.

Suggested change

	```bash
	mv .claude .gemini
	```
	4. In `settings.json`, update the permission keys to match Gemini CLI:
	```json
	{
	"permissions": {
	"allow": [
	"read_file",
	"list_directory",
	"write_file",
	"web_fetch",
	"web_search"
	]
	}
	}
	```
	```bash
	mv .claude .gemini

4. In settings.json, update the permission keys to match Gemini CLI:

   {
     "permissions": {
       "allow": [
         "read_file",
         "list_directory",
         "write_file",
         "web_fetch",
         "web_search"
       ]
     }
   }

[Copilot]

Step 4 references settings.json generically, but after renaming .claude to .gemini the file path would be .gemini/settings.json (not a root-level settings.json). Also, these are permission values in the allow array rather than “permission keys” — consider adjusting wording to avoid confusion.

Suggested change

	4. In `settings.json`, update the permission keys to match Gemini CLI:
	4. In `.gemini/settings.json`, update the permission values in the `permissions.allow` array to match Gemini CLI:

[Copilot]

The paragraph after the options still says “For both options”, but there are now three setup options (Claude, Codex, Gemini). Update this phrasing to “For all options” (or similar) so the README stays consistent.

Suggested change

	For both options, the coach will ask for your resume, target role, and timeline — then build your profile, assess your starting point, and give you a prioritized action plan. Everything saves automatically to `coaching_state.md` so you pick up where you left off next session.
	For all options, the coach will ask for your resume, target role, and timeline — then build your profile, assess your starting point, and give you a prioritized action plan. Everything saves automatically to `coaching_state.md` so you pick up where you left off next session.

[Copilot]

This new Gemini setup introduces GEMINI.md as an alternative activation filename, but later in the README “Repository Structure” still says to rename SKILL.md to CLAUDE.md to activate. Consider updating that later section to reflect all supported activation filenames so the documentation doesn’t contradict itself.