Fix timer not starting after v3.6.0 update

[gloriafolaron]

Summary

• Re-enables the stopwatch partial in header menu (was commented out, causing htmx:targetError)
• Fixes variable name passed to stopwatch partial (progressSteps → onTheClock)
• Adds error handling for punchIn failures (catches QueryException, validates session)
• Shows success/error notifications when starting timer
• Fixes template syntax (false|null → false)

Root Cause

The stopwatch partial in headMenu.blade.php was commented out, so the #timerHeadMenu element didn't exist. All timer buttons use hx-target="#timerHeadMenu", causing HTMX to fail silently.

Test plan

• Start timer from My Work dashboard
• Start timer from project kanban view (three-dot menu)
• Start timer from company timesheets
• Verify timer appears in header
• Stop timer and verify time logged

Fixes #3208

🤖 Generated with Claude Code

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