tools: project-browser: add address bar

[KaindraDjoemena]

Adds an address bar with back/forward navigation buttons to the project browser panel, as described in the issue.

Changes:

• Added back (<) and forward (>) navigation buttons
• Added address bar showing the current folder path (e.g. /parentFolder/childFolder/)
• Navigation with the address bar
• Address bar updates when clicking folders in the tree view
• Address bar shows parent folder when a file is selected
• Invalid paths are rejected and logged to the console

Screenshot:

Closes #216

[KaindraDjoemena]

Note: uncrustify reformatted a bunch of the code, resulting in a big diff file. Here are the changes i made:

• New fields: _nav_history_back, _nav_history_forward, _navigating_history, _btn_back, _btn_forward, _address_bar
• New methods: navigate_to, navigate_back, navigate_forward
• Modified: ProjectBrowser constructor (nav bar UI), on_open_directory, _tree_selection.changed handler

[dbartolini]

A problem is sometimes buttons need two clicks to activate:

Screencast.From.2026-03-09.16-27-57.mp4

Formatting problem is odd since project_browser.vala is excluded from linting:

crown/scripts/uncrustify/format-all.sh

Line 25 in c8c732a

| grep -v 'project_browser.vala' \

Use git reset HEAD~ && git add -p to add only relevant changes.