Update project language and site toolchain

[dbtlr]

What changed

• Reframed Norn, Mimir, Saga, and Skald as separate project stories instead of one bundled tool family.
• Updated Saga copy from plugin/orchestration language to agent-memory / memory-provider language.
• Removed cross-project split/family phrasing from Mimir, Skald, homepage, about, and projects index copy.
• Bumped site toolchain dependencies: Astro, Tailwind, Tailwind Vite plugin, and Wrangler.

Why

Saga has shifted from a plugin/skill-set framing to a memory-provider framing, and the site copy needed to reflect that without presenting Norn, Mimir, and Saga as one layered product.

The dependency bump also removes the Node 26 DEP0205 warning from Tailwind's module.register() usage.

Validation

• pnpm outdated
• pnpm check
• pnpm build
• NODE_OPTIONS=--trace-deprecation pnpm check

[github-actions]

🔎 Preview deploy

https://380522c0-dbtlr-com.dbs-account.workers.dev

_{Updated for c5740b2 · ephemeral version, not production.}