feat(browser): improve browser profile management and cleanup

Enhance browser profile handling with better process cleanup and documentation:
- Add process cleanup for existing Chromium instances on Windows/Unix
- Fix profile creation by passing complete browser config
- Add comprehensive documentation for browser and CLI components
- Add initial profile creation test
- Bump version to 0.6.3

This change improves reliability when managing browser profiles and provides better documentation for developers.

docs/codebase/cli.md

@@ -0,0 +1,40 @@
+### `cli.py` command surface
+
+| Command | Inputs / flags | What it does |
+|---|---|---|
+| **profiles** | *(none)* | Opens the interactive profile manager, lets you list, create, delete saved browser profiles that live in `~/.crawl4ai/profiles`. |
+| **browser status** | – | Prints whether the always-on *builtin* browser is running, shows its CDP URL, PID, start time. |
+| **browser stop** | – | Kills the builtin browser and deletes its status file. |
+| **browser view** | `--url, -u` URL *(optional)* | Pops a visible window of the builtin browser, navigates to `URL` or `about:blank`. |
+| **config list** | – | Dumps every global setting, showing current value, default, and description. |
+| **config get** | `key` | Prints the value of a single setting, falls back to default if unset. |
+| **config set** | `key value` | Persists a new value in the global config (stored under `~/.crawl4ai/config.yml`). |
+| **examples** | – | Just spits out real-world CLI usage samples. |
+| **crawl** | `url` *(positional)*<br>`--browser-config,-B` path<br>`--crawler-config,-C` path<br>`--filter-config,-f` path<br>`--extraction-config,-e` path<br>`--json-extract,-j` [desc]\*<br>`--schema,-s` path<br>`--browser,-b` k=v list<br>`--crawler,-c` k=v list<br>`--output,-o` all,json,markdown,md,markdown-fit,md-fit *(default all)*<br>`--output-file,-O` path<br>`--bypass-cache,-b` *(flag, default true — note flag reuse)*<br>`--question,-q` str<br>`--verbose,-v` *(flag)*<br>`--profile,-p` profile-name | One-shot crawl + extraction. Builds `BrowserConfig` and `CrawlerRunConfig` from inline flags or separate YAML/JSON files, runs `AsyncWebCrawler.run()`, can route through a named saved profile and pipe the result to stdout or a file. |
+| **(default)** | Same flags as **crawl**, plus `--example` | Shortcut so you can type just `crwl https://site.com`. When first arg is not a known sub-command, it falls through to *crawl*. |
+
+\* `--json-extract/-j` with no value turns on LLM-based JSON extraction using an auto schema, supplying a string lets you prompt-engineer the field descriptions.
+
+> Quick mental model  
+> `profiles` = manage identities,  
+> `browser ...` = control long-running headless Chrome that all crawls can piggy-back on,  
+> `crawl` = do the actual work,  
+> `config` = tweak global defaults,  
+> everything else is sugar.
+
+### Quick-fire “profile” usage cheatsheet
+
+| Scenario | Command (copy-paste ready) | Notes |
+|---|---|---|
+| **Launch interactive Profile Manager UI** | `crwl profiles` | Opens TUI with options: 1 List, 2 Create, 3 Delete, 4 Use-to-crawl, 5 Exit. |
+| **Create a fresh profile** | `crwl profiles` → choose **2** → name it → browser opens → log in → press **q** in terminal | Saves to `~/.crawl4ai/profiles/<name>`. |
+| **List saved profiles** | `crwl profiles` → choose **1** | Shows name, browser type, size, last-modified. |
+| **Delete a profile** | `crwl profiles` → choose **3** → pick the profile index → confirm | Removes the folder. |
+| **Crawl with a profile (default alias)** | `crwl https://site.com/dashboard -p my-profile` | Keeps login cookies, sets `use_managed_browser=true` under the hood. |
+| **Crawl + verbose JSON output** | `crwl https://site.com -p my-profile -o json -v` | Any other `crawl` flags work the same. |
+| **Crawl with extra browser tweaks** | `crwl https://site.com -p my-profile -b "headless=true,viewport_width=1680"` | CLI overrides go on top of the profile. |
+| **Same but via explicit sub-command** | `crwl crawl https://site.com -p my-profile` | Identical to default alias. |
+| **Use profile from inside Profile Manager** | `crwl profiles` → choose **4** → pick profile → enter URL → follow prompts | Handy when demo-ing to non-CLI folks. |
+| **One-off crawl with a profile folder path (no name lookup)** | `crwl https://site.com -b "user_data_dir=$HOME/.crawl4ai/profiles/my-profile,use_managed_browser=true"` | Bypasses registry, useful for CI scripts. |
+| **Launch a dev browser on CDP port with the same identity** | `crwl cdp -d $HOME/.crawl4ai/profiles/my-profile -P 9223` | Lets Puppeteer/Playwright attach for debugging. |
+