- types.mdx: "seven" → "seven base types + one SQL composite",
add observer_window section with field table and usage example
- operators-gist.mdx: "three operators" → "four operators", reframe
SP-GiST performance as scalability feature (honest about seqscan
being faster at 14k catalog size, index helps at 100k+)
- installation.mdx: "14 test suites" → "15 test suites", list all
suites including od_fit, spgist_tle, vallado_518
- design-principles.mdx: clarify observer_window is SQL composite
(variable-length, query-time only), base types still STORAGE=plain
- pass-prediction.mdx: lead with operator value (80-90% elimination),
SP-GiST index framed as optional for large catalogs