[iwis19]

Description

Resolves #21, needs more work on final UI design

Adds watcloud du to watcloud-cli. Opens an interactive, sorted view of user's home directory and helps users find what is consuming their storage quota.

Top of the interface shows user's current directory path, total quota, etc at any depth. All entries are sorted largest first and show their size and percentage of the home quota. Directory sizes come from CephFS metadata instead of recursive filesystem scans.

Commands	Actions
Up/Down arrows	Select item
Enter/Right	Open folder
Backspace/Left	Go back
r	Refresh
q / Escape / Ctrl C	Quit

The command keeps browsing within the home directory and its mount without following symlinks. It also handles unavailable sizes, unreadable entries, and missing/unlimited quotas. More error handling were tested, but not committed.

The UI is currently built with Bubble Tea, and its kept minimalistic since we probably need to unify the CLI UI design altogether anyways afterwards.

Tests Performed

No lagging / stuttering while running ./watcloud du on own directory.
Allows q Quit when file loading is stuck.

Uncommitted go test passed (performance on larger directories, error handling, etc):

1. benchmark_test.go
2. browser_test.go
3. du_test.go

Checklist

• I have read and understood the WATcloud Guidelines
• I have performed a self-review of my code

[feinburger244]

I will try to get to this on Sunday