Improve local path hover and click behavior

[mac0ne]

What do you want to change?

About myself:

New Ghostty nighty build user. Product manager and developer.

What I'd like to work on:

Tiny improvement for local path hover/click behavior.

Problem:

1. Path overmatch in prompts: text like "(base) foo@bar|~/Documents/proj on main!?" was matched as one path.
2. Missing local file link detection, for example, ls -l output and the file name/path that appear in the console could be clickable and openable.

Expected behavior:

1. the test case in above case should match only ~/Documents/proj.
2. Local and existing files should be click-openable.

Fixes:

1. Regex refinements in url.zig
2. Local-path existence gating in Surface.zig
3. Open normalization fix in Surface.zig (TODO: passing line/column as arguements when launching editors that support it, this is an iTerm2 feature).

I've implemented above fixes at:
Branch: fix/local-path-link-detection
Commit: 62162d6
Code: https://github.com/mac0ne/ghostty/tree/fix/local-path-link-detection

Validation:

1. zig build test -Dtest-filter="url regex"
2. zig build test

AI usage disclosure:

1. I used OpenAI Codex (GPT-5.3-Codex) for AI-assisted code editing and text drafting and Claude Code with Opus 4.6 for code review.
2. Extent: initial implementation and wording assistance.
3. I manually reviewed and edited the code/text and I understand how the changes work in src/config/url.zig and src/Surface.zig.

Why do you want to make this change?

I was primarily using iTerm2 on my macOS and this feature is frequently used feature so I could open paths/files from the terminal emulator directly. With this change, Ghostty doesn't break my experience.

I acknowledge that:

• I have read the Contributing Guide and understand the contribution process.
• I have read and agree to follow the AI Usage Policy.
• I wrote this vouch request myself, in my own voice, without AI generating it.

[mitchellh]

!vouch