[botandbang]

This adds TSDoc support to the doc checks and to the stubs that --fix and the language server write. It doesn't validate TSDoc grammar or read tsdoc.json.

Added:

• A syntax key ("jsdoc" by default, or "tsdoc"), registered as its own feature file. With "tsdoc", stubs write @typeParam T -, @param x - and @packageDocumentation in place of @template T, @param x and @file, require-template asks for @typeParam in its findings, and valid-link reads the A in {@link A#b} as a package name and doesn't look it up. With "jsdoc", A is still a class the file has to declare. The key is in the regenerated docov.schema.json, the README and --print-config, and the cache stamps by it.
• A TSDoc-style fixture (tests/fixtures/tsdoc/parser.ts) that passes every doc check at error with "syntax": "tsdoc", plus unit tests and Hegel properties for each change below.

Changed:

• require-template counts @typeParam T - desc and @typeParam T as naming T.
• empty-tag-description also checks @typeParam, and ignores the - TSDoc puts between a name and its description, so @param x - has no description. A - with no space after it, as in -1, stays part of the text.
• An inline {@inheritDoc} or {@inheritDoc Ref} in a block's description or any tag's text now means the item inherits its docs, the same as the @inheritdoc block tag, unless it's escaped or inside a code span. One helper decides this for both coverage and the checks that leave inheriting blocks alone, and the escape and code-span test is shared with valid-link.
• summary-sentence leaves a block that inherits its docs alone. Before this, /** {@inheritDoc Base.m} */ was reported as a summary without a period.
• valid-link gives no findings for {@link Foo.bar | text}, {@link @scope/pkg#Foo}, {@link (Foo:constructor)} and {@link Foo.(bar:static)} in either syntax, and none for {@link pkg#Foo.bar} with "syntax": "tsdoc".
• The inherit key's docs and schema mention the inline form.

Removed:

• Nothing.