prolog: integration test suite (+20)

20 end-to-end tests via pl-query-* API: permission system, graph
reachability, quicksort, dynamic KB, fibonacci. Total 571/571.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

plans/prolog-on-sx.md

@@ -74,7 +74,7 @@ Representation choices (finalise in phase 1, document here):
 ### Phase 5 — Hyperscript integration
 - [x] `prolog-query` primitive callable from SX/Hyperscript
 - [ ] Hyperscript DSL: `when allowed(user, :edit) then …` ← **blocked** (needs `lib/hyperscript/**`, out of scope)
-- [ ] Integration suite
+- [x] Integration suite
 
 ### Phase 6 — ISO conformance
 - [x] Vendor Hirst's conformance tests
@@ -88,6 +88,7 @@ Representation choices (finalise in phase 1, document here):
 
 _Newest first. Agent appends on every commit._
 
+- 2026-05-05 — Integration test suite (`tests/integration.sx`): 20 end-to-end tests via `pl-query-*` API covering permission system (6), graph reachability (4), quicksort (4), fibonacci (3), dynamic KB (3). Suite added to conformance harness. Total **571** (+20).
 - 2026-04-25 — `pl-compiled-matches-interp?` cross-validator in `compiler.sx`: loads source into both a plain and a compiled DB, runs the same goal, returns true iff solution counts match. `tests/cross_validate.sx` applies this to 17 goals across append/member/ancestor/cut/arithmetic/if-then-else, locking the interpreter as the reference against which any future compiler change must agree. Total **551** (+17).
 - 2026-04-25 — Clause compiler (`lib/prolog/compiler.sx`): `pl-compile-clause` converts parse-AST clauses to SX closures `(fn (goal trail db cut-box k) bool)`. Pre-collects var names at compile time; `pl-cmp-build-term` reconstructs fresh runtime terms per call. `pl-compile-db!` compiles all clauses in a DB and stores them in `:compiled` table. `pl-solve-user!` in runtime.sx auto-dispatches to compiled lambdas when present, falls back to interpreted. `pl-try-compiled-clauses!` mirrors `pl-try-clauses!` cut semantics. 17 tests in `tests/compiler.sx`. Total **534** (+17).
 - 2026-04-25 — `predsort/3` (insertion-sort with 3-arg comparator predicate, deduplicates `=` pairs), `term_variables/2` (collect unbound vars left-to-right, dedup by id), arithmetic extensions (`floor/1`, `ceiling/1`, `truncate/1`, `round/1`, `sign/1`, `sqrt/1`, `pow/2`, `**/2`, `^/2`, `integer/1`, `float/1`, `float_integer_part/1`, `float_fractional_part/1`). 21 tests in `tests/advanced.sx`. Total **517** (+21).