Fix bracket/brace filenames breaking LSP features

[andriytyurnikov]

Fixes #4023
Fixes #3503

Motivation

Files with [, ], {, or } in their names (e.g., [id].rb, {slug}.rb — common in Rails/Next.js routing conventions) break multiple ruby-lsp features. The root cause is twofold:

1. URI encoding mismatch: Brackets are not percent-encoded in URIs, but VS Code's vscode-uri always encodes them ([ → %5B, ] → %5D). This creates a URI mismatch that prevents the store from finding documents.
2. Glob metacharacters: Brackets and braces are Dir.glob metacharacters ([id] is interpreted as a character class matching i or d), breaking file discovery when paths contain these characters.

When a file like app/[id].rb exists, all LSP features fail for that file — indexing, go-to-definition, references, hover, completion, diagnostics, code lens, etc.

Changes

URI encoding fix

• Removed [] from the safe character set in URI::Generic.from_path so brackets are percent-encoded, matching VS Code's encoding (as identified by @streetpaws in Linux file system with square brackets in the directory/filename are failing to be indexed #3503). Braces were already correctly encoded. The to_standardized_path method already calls PARSER.unescape(), so the round-trip (path → URI → path) works without additional changes.

Dir.glob hardening

• Used Dir.glob's base: parameter in references.rb, rename.rb, addon.rb, test_style.rb, and go_to_relevant_file.rb so workspace/file paths are treated as literal filesystem paths rather than glob patterns.
• Escaped glob metacharacters in user-provided require_relative content before interpolating into glob patterns in the completion listener.
• Escaped glob metacharacters in filenames used to build search patterns in go_to_relevant_file.rb.

Test runner fix

• Replaced Dir.glob with File.file? checks for expectation file lookup in the expectations test runner, so bracket-named fixtures don't break.
• Sanitized fixture names in generated test method names ([id] → _id_) to prevent syntax errors.

Tests

• Added URI unit tests for brackets, braces, parentheses, and whitespace-within-delimiter round-trips.

Not included

configuration.rb glob calls were not converted to base: due to a Ruby Dir.glob bug with empty brace patterns — tracked in #4024.

Test plan

• bin/test lib/ruby_indexer/test/uri_test.rb — all 23 URI tests pass
• bundle exec rake — full test suite passes (322 runs, 0 failures)
• bundle exec srb tc — Sorbet type check passes
• bin/rubocop — no offenses