Add clipboard copy for log message and full entry (ctrl+y / y)

[soy-chrislo]

Fixes #9

What

In the log details modal:

• y (or alt+y) copies just the log message to the clipboard.
• ctrl+y copies the full entry as plain text: severity, timestamps, attributes (sorted alphabetically, same as the attributes table), and the AI analysis result if one has already been run for this entry.

Both are plain text (no ANSI/lipgloss styling), so they paste cleanly into Slack, an AI chat, or a bug report — matching the use case described in the issue.

Design

This follows what was discussed in the issue thread: atotto/clipboard (it was already an indirect dependency, now promoted to direct via go mod tidy), ctrl-y for the full log, y/alt-y for the message.

One deliberate deviation worth flagging: instead of adding a separate binding for "copy AI analysis" in the chat pane, I folded it into ctrl+y — the AI analysis already renders in the same info pane as the rest of the log details, so copying "everything visible here" felt like the more natural fit. Happy to split it into its own key if you'd rather keep it separate.

I intentionally left the chat pane untouched — it captures every keystroke while focused for typing, and scoping this to the info pane kept the change small and avoided fighting that input-focus behavior.

Testing

• Added internal/tui/clipboard_test.go (table-driven, matching the only existing test file's style) covering the plain-text formatting (attribute sorting, optional Log Time/Attributes/AI Analysis sections, and skipping the transient "Analyzing..." placeholder).
• make fmt, make vet, make test, make build all pass locally.
• Manually verified end-to-end on Linux/Wayland: copied from the running app and confirmed the exact content lands in the clipboard via wl-paste.

Known limitation: atotto/clipboard needs xclip/xsel/wl-copy on Linux (no OSC52 fallback) — on failure, the status bar shows "Copy failed: ..." instead of silently doing nothing.

[soy-chrislo]

Hope this resolves the issue! Happy to make any changes needed to get it merged — just let me know and I'll get on it.

One small heads-up from testing: on my machine, pasting into Kate (KDE) specifically doesn't pick up the multi-line ctrl+y copy, though the single-line y copy works fine there, and other apps read the multi-line one correctly. Seems like a Kate/Wayland clipboard quirk unrelated to this PR — just flagging it in case it's useful, not something I think needs fixing here.

[rbg]

Thanks for the PR and heads up - we'll take a look !