Proposal: CLI install command with interactive setup wizard (#287)

* propose: CLI install command with interactive setup wizard

Add proposal for `java-codebase-rag install` and `update` subcommands.
Interactive 6-stage pipeline: Java source detection, embedding model,
agent host selection (Claude Code / GigaCode / Qwen Code), install scope,
artifact deployment, and project indexing. Non-interactive mode for CI.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

* improve CLI install proposal: validation, re-run semantics, exit codes

- Add MCP entrypoint validation (shutil.which check after deploy)
- Define re-run behavior: pre-fill existing values, preserve unmanaged YAML keys
- Clarify exit codes with user action guidance
- Require explicit confirmation for missing model paths (y/n instead of warn-only)
- Add platform notes and per-artifact writability checks

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

* plan: CLI install command (2-PR sequence: I1 install + I2 update)

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

* fill gap: resolve java-codebase-rag-mcp absolute path before writing MCP config

The install pipeline now resolves the MCP entrypoint's absolute path via
shutil.which() before writing it into the agent host's MCP config. This
ensures the config works regardless of the agent host's PATH (GUI launchers,
virtualenvs, pip --user installs). Interactive mode prompts for a manual
path if auto-detection fails; non-interactive mode exits with code 2.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

* add source_root interactive confirmation to install plan

Stage 1 now prompts the user to confirm or change the source root
(defaulting to cwd). Non-interactive mode skips the prompt. index_dir
remains implicit. Adds 5 new tests and renumbers existing ones to 47.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

* Update CLI install proposal and plan: multi-host + module detection

Multi-host support:
- Stage 3 changed from single-select menu to checkbox (all hosts pre-selected)
- Non-interactive mode accepts multiple --agent flags
- Deploy artifacts to all selected hosts in a single run
- Added multi-host test cases

Module detection simplification:
- Detect at Maven/Gradle build file level (pom.xml, build.gradle*)
- Root has build file? Show only "." (entire project as one unit)
- Root has no build file? Show immediate children with build files
- Prevents overwhelming users with nested Maven modules in large projects
- Updated test cases to reflect simplified detection logic

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

* Move CLI-INSTALL-PROPOSE.md to completed folder

Proposal design is finalized with multi-host support and simplified module detection.
Moving to completed/ as the proposal phase is done.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

* fix: resolve all 9 PR review issues in CLI install proposal and plan

- Remove stale `rich>=13.0` dependency from proposal (use existing cli_format.py)
- Fix duplicate test #12 in plan (renumber tests 13-54)
- Remove nested module detection test case (contradicts "no recursive descent")
- Move proposal from completed/ back to active/ (per AGENTS.md)
- Fix test numbering in implementation step list to match renumbered tests
- Resolve [TBD] Open Questions (present as resolved decisions)
- Fix update command to use non_interactive=True (non-interactive by default)

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

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Co-authored-by: Claude Opus 4.7 <noreply@anthropic.com>

Author: HumanBean17