BUG: Generated files are tracked and required runtime dependencies are missing

### Is there an existing issue for this?

- [x] I have searched the existing issues

### What happened?

## 📌 Issue Overview

Several generated, environment-specific, and machine-specific files are tracked because the repository's `.gitignore` rules are incomplete.

These include frontend environment configuration, ChromaDB data, backend cache files, editor settings, macOS metadata, and Bundler configuration. Tracking these files creates unnecessary changes, repository bloat, configuration conflicts, and a risk of exposing sensitive values.

Additionally, runtime dependencies already used by the application are missing from the dependency manifests:

- The frontend uses AsyncStorage but does not declare `@react-native-async-storage/async-storage`.
- The backend imports ChromaDB but does not declare `chromadb` in `requirements.txt`.

Consequently, a fresh installation can fail even after installing all declared dependencies.

## 🔍 Steps to Reproduce

### Generated and tracked files

1. Clone the repository.
2. Install and run the frontend and backend.
3. Configure the frontend `.env` file and run ChromaDB-dependent features.
4. Open the project in VS Code or on macOS.
5. Run `git status`.
6. Observe generated or machine-specific files being tracked or appearing as changes.

### Missing dependencies

1. Install the frontend dependencies using `npm install`.
2. Run the React Native application.
3. Observe that AsyncStorage cannot be resolved because it is missing from `package.json`.
4. Install the backend dependencies using `pip install -r requirements.txt`.
5. Run the backend functionality that imports ChromaDB.
6. Observe `ModuleNotFoundError: No module named 'chromadb'`.

## 🎯 Expected Behavior

Generated databases, caches, environment files, virtual environments, editor settings, and machine-specific configuration should be ignored by Git.

Running or configuring the project should not create unrelated changes in the working tree.

All runtime dependencies used by the frontend and backend should be declared and pinned in their respective dependency manifests so a fresh installation can run successfully.

## 🚨 Actual Behavior

The repository tracks files such as:

- `.DS_Store`
- `.vscode/`
- `Frontend/.env`
- `Frontend/.bundle/config`
- `Backend/db/chromadb/chroma.sqlite3`
- `Backend/cache/context_default.json`
- `Backend/tests/cache/context_default.json`

The backend `.gitignore` also contains incomplete patterns for Python virtual environments, bytecode, databases, and cache directories.

Additionally:

- `@react-native-async-storage/async-storage` is missing from `Frontend/package.json`.
- `chromadb` is missing from `Backend/requirements.txt`.
- Installing the declared dependencies alone does not provide every module required by the application.

## 📷 Screenshot

## 💡 Suggested Improvements

- Add `.DS_Store` and `.vscode/` to the root `.gitignore`.
- Ignore `.venv/`, `venv/`, `env/`, `__pycache__/`, and `*.py[cod]`.
- Ignore backend SQLite databases, ChromaDB data, and generated cache directories.
- Ignore `Frontend/.bundle/`.
- Remove already tracked generated and environment-specific files from the Git index.
- Keep only reproducible source code and safe configuration templates under version control.
- Add `@react-native-async-storage/async-storage@2.1.2` to the frontend dependencies.
- Synchronize `Frontend/package-lock.json`.
- Declare the required ChromaDB dependency in `Backend/requirements.txt`.
- Normalize `Backend/requirements.txt` to UTF-8.

> [!WARNING]
> Security scanners currently report critical advisories affecting `chromadb==1.5.9`, with no patched release available. The selected ChromaDB version should therefore receive maintainer review and the alerts should not be suppressed.

### Record

- [x] I agree to follow this project's Code of Conduct
- [x] I want to work on this issue

Start by reviewing the root .gitignore, the backend ignore rules, Frontend/package.json, Frontend/package-lock.json, and Backend/requirements.txt, then reproduce the clean-install and git-status steps from the issue. Check the listed tracked files and dependency imports before making changes. Done means generated and machine-specific files no longer appear as changes and fresh frontend and backend installs declare the runtime dependencies, with the ChromaDB security warning reviewed by a maintainer.

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