Use alignment specification for our linking

https://github.com/bible-technology/scripture-burrito/blob/develop/docs/flavors/alignment_flavor.rst

Linking: analyses to text; text to lexicon

For the latter: the flavor's Reference Schemes section, and Appendix 1 of the format it delegates to, bible-technology/alignment-spec.

Timing note: AlignmentLink is currently dead weight in the best sense — no feature writes it, drafts don't carry links, and no UI renders alignments. The cost of adopting or mapping to the Burrito alignment flavor is therefore near zero today and grows with every feature that touches alignment. Recommend doing this investigation before an alignment-editing UI is scheduled.

Scope:

• (a) can our AlignmentLink/AlignmentEndpoint round-trip to the Burrito flavor?
• (b) do its reference schemes fit our text-to-lexicon refs (EntryRef/SenseRef)? — answered in the findings; #225 depends on it [moved into the scope of #225]
• (c) what changes, if any, to §5 of interlinearizer.d.ts?

Size: S (investigation + written recommendation)

Where to read the spec: the alignment flavor lives on scripture-burrito@develop and is absent from the published v1.0.0 tag, so every docs.burrito.bible URL for it 404s — read it in the repo. The flavor page also runs ahead of alignment-spec, the format it delegates to, so read both rather than spec.md alone. v1.0.0's parascriptural_word_alignment is the deprecated predecessor the alignment flavor supersedes — container metadata only, no reference model — and is out of scope here.