feat(formulation): expose queryParamPushdown + pushdown apply helper; make pagination fully drivable

[jeffreyaven]

What

Additive, backward-compatible OData query-option push-down + pagination scaffolding for downstream stackql (stackql #659, #677, #591). Closes #105.

A. Expose QueryParamPushdown on the public surface

• Add GetQueryParamPushdown() (QueryParamPushdown, bool) to the public OperationStore.
• Add public interfaces QueryParamPushdown, SelectPushdown, FilterPushdown, OrderByPushdown, TopPushdown, SkipPushdown, CountPushdown (internal JSONLookup omitted).
• Wrapper accessors on wrappedOperationStore/wrappedStandardOperationStore + wrapped*Pushdown delegates.
• Honours the existing Method -> Resource -> Service -> ProviderService -> Provider inheritance.

B. Dialect-aware translation/apply helper

• ApplyPushdown(PushdownConfigSource, PushdownIntent) PushdownResult: neutral input struct, interface-typed result (no mutable carrier leaked).
• Partial-pushdown contract: unsupported columns/operators/dialects fall to ResidualPredicates; projection/order-by are all-or-nothing.
• OData: $filter (eq/ne/gt/ge/lt/le/startswith/endswith/contains joined by and), $select, $orderby, $top (clamped to maxValue), $skip (clamped to maxValue), $count=true (+ response key). Custom dialect uses configured param names only. Absent config = no-op, all predicates residual.

C. SkipPushdown (closes #105 part 1)

• internal/anysdk/query_param_pushdown.go: SkipPushdown interface + standardSkipPushdown (dialect/paramName/maxValue), $skip default, GetSkip(), struct field, JSONLookup case. SQL OFFSET N -> OData $skip=N.

D. odata_next_link pagination algorithm (closes #105 part 2)

• internal/anysdk/pagination.go: PaginationAlgorithmODataNextLink = "odata_next_link" registered constant. Caller drives the follow/strip/terminate loop using the public Pagination / TokenSemantic accessors, mirroring page_number (no engine code in any-sdk).

E. Pagination drivability

• Add GetAlgorithm() and GetArgs() map[string]interface{} to public TokenSemantic (args as a plain map). page_number (request key + start value + total_pages terminator), @odata.nextLink, and $skip offset are all drivable through the public surface.

F. GraphQL LIMIT push-down

• Verified only, no change: NewStandardGQLReaderFull substitutes constInput (paramMap) into the query template via text/template, so stackql can inject a SQL LIMIT as a query variable.

Tests

• Internal: SkipPushdown (OData defaults / custom / absent) + odata_next_link constant pin.
• Public: pushdown apply (full OData, partial/residual, custom dialect, count, top clamp, skip full/clamp/custom/absent, absent-config no-op) + page_number / @odata.nextLink / $skip drivability.

Notes

• page_number stop condition: result_info.page >= result_info.total_pages (responseToken vs responseTerminator).
• Suggested release tag after merge: v0.5.3-alpha07 (keeps v0.5.3-alpha06 pagination accessors intact).

additional changes

Bumped all actions/* GitHub Actions to their latest major floating tags to clear the Node 20 deprecation warnings (now all run on Node 24): checkout v7, setup-go v6, setup-python v6, upload-artifact v7, download-artifact v8 (build.yml, provider-analysis.yml, mock-experiment.yml). setup-go v6 enables module caching by default, and these jobs run setup-go before checkout (no go.mod yet), so added cache: false to the setup-go steps to restore prior no-cache behaviour and avoid a "Dependencies file is not found" warning. Left google-github-actions/*, snok/install-poetry, and the app-managed claude.yml untouched. The macos-latest migration notice is an informational GitHub runner-image message unrelated to these changes (resolvable only by pinning a specific macOS runner label).

Closes #105.