feat(#7): Phosphor Cyan dark theme overhaul #11

Replaces DaisyUI pastel theme with custom 'forest' dark theme.
Semantic design tokens in @theme block: change 6 color values
for a full revamp. Graph-paper grid texture on body.
Card left-border accent replaces rounded corners.

Drop Oswald and Shadows Into Light Two; load Aldrich from Bunny Fonts.
Remove duplicate font preload in +layout.svelte.

Sections:
- LatestProjects bg-white → bg-base-200
- Portfolio bg-neutral-content → bg-base-200, remove rounded-2xl, green hover overlay
- ProjectCard border hover primary-content → primary
Tabs/Tab:
- Remove rounded-full from container and pill classes
- text-black → text-base-content, tabs bg-neutral-content → bg-base-300
- Active tab uses !text-primary-content to force contrast on bg-primary
Timeline (ExperienceSection):
- Replace circle-check SVG icons with square div markers (bg-primary / border-primary)
- Company name text-primary-content → text-primary
Publications/Skills:
- text-primary-content → text-primary on icons and author labels
- badge border-radius overridden to 0 in app.css
- hover:badge-primary on skill items
app.css:
- Add .badge, .alert to border-radius: 0 override
- Fix step circle: .step::before → .step::after (DaisyUI v5 uses ::after)
- Add .tabs, .tab border-radius: 0 override
Navbar/Hero:
- border-leaf-bright → border-primary (semantic token)
- Active state uses color-mix instead of raw oklch var

- Contact section bg-neutral-content → bg-base-200
- Portfolio tooltip borders border-primary-content → border-primary (visible green)
- Tab: remove redundant class: bindings (bg-primary, text-primary-content, font-semibold) already handled in $: classes
- +layout.svelte: add data-theme="forest" to root wrapper