Fix searching for standalone symbolic entries

[Ethereal49]

Searching Clojure for -> normalizes both the entry name and query to ., which is then rejected as a separator-only query. Preserve a standalone symbolic name when separator normalization would consume the entire name, after stripping the existing decorations. Compound names still use the existing separator normalization and ranking rules.

Fixes #817.

Added regression coverage for standalone symbols, decorated symbolic names, Clojure operators, member separators, namespaces, exact/fuzzy ranking, and the existing suppression of empty and dot-only queries. The new regressions fail on the original searcher.

Validation:

• npm test: 47 passed, no skipped tests.
• npm run typecheck: passed for assets and tests.
• Current published Clojure 1.11 index (989 entries): reproduced zero results before the change and a correct -> match afterward through the actual Entry/Search/asynchronous Searcher modules in an isolated browser harness.
• Compared complete ordered results for all 964 distinct Clojure entry-name queries, plus selected queries over current PHP, C++, JavaScript and the combined 16,721-entry index. Only -> becoming searchable and - additionally matching that entry changed; existing separator queries and relative ranking remained consistent.

The full Sinatra/Ruby app and Ruby suite were not run because the local Ruby/Bundler versions do not meet the repository requirements. The browser check used an isolated module harness with test replacements for generated config/templates, rather than the full site. Existing . and .. query suppression is unchanged.

Prepared with OpenAI Codex assistance; the automated tests, typechecks and isolated browser checks above were performed locally.

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