`docs-data` compile fails on clean `develop`: "nav.json references page 'core' which does not exist in docs.pages"

Environment

• Package version(s): develop branch (tested at commit 1230046b7)
• Operating System: Windows 11
• Browser name and version: N/A, this is a build-time failure, not a runtime/browser issue

Code Sandbox

N/A, this bug occurs during the docs-data compile step (pnpm nx run @blueprintjs/docs-data:compile, also triggered by pnpm dev), before any browser rendering happens. A CodeSandbox repro isn't applicable; see reproduction steps below instead.

Steps to reproduce

1. Clone the repo fresh and check out develop
2. pnpm install
3. pnpm nx run @blueprintjs/docs-data:compile (or pnpm dev, which depends on this task)

Actual behavior

The compile step fails consistently, even on a completely clean checkout with zero local changes (confirmed via git status):

[docs-data] compiling documentation for library packages: core, datetime, datetime2, icons, select, table, labs [docs-data] successfully generated npm-data.json Found duplicate page "index"; overwriting previous data. Rename headings or use metadata reference key to disambiguate. Found duplicate page "index"; overwriting previous data. Rename headings or use metadata reference key to disambiguate. ... [warning] You are running with an unsupported TypeScript version! If TypeDoc crashes, this is why. TypeDoc supports 4.6, 4.7, 4.8, 4.9, 5.0, 5.1, 5.2, 5.3, 5.4 ... [docs-data] ERROR when generating JSON docs data: C:...\packages\docs-data\compile-docs-data.mts:52 throw new Error(err); ^ Error: Error: [docs-data] nav.json references page "core" which does not exist in docs.pages at (C:...\packages\docs-data\compile-docs-data.mts:52:11)

Expected behavior

docs-data should compile successfully on a clean develop checkout, since this blocks pnpm dev (the full docs app depends on this task), making local manual/browser verification of changes difficult.

Possible solution

Two possible leads, though I haven't dug in deep enough to confirm either:

1. The repeated Found duplicate page "index"; overwriting previous data warnings for multiple packages, right before the crash, suggest several packages are generating a docs page under the same "index" key. By the time nav.json looks up the "core" page, it may have already been overwritten by one of these collisions.
2. The repo currently resolves TypeScript 5.9.3, while the [warning] You are running with an unsupported TypeScript version! message indicates TypeDoc only supports up to 5.4. This mismatch could be a contributing factor.

Confirmed reproducible after pnpm nx reset and clearing packages/docs-data/dist and other generated artifacts, so it isn't a stale-cache issue.