Add yard config and linter

.gitignore

@@ -71,3 +71,6 @@ dump.rdb
 
 # Ignore schema file, it's database-dependent and Manyfold shouldn't be
 db/schema.rb
+
+.yardoc
+doc

.yard-lint.yml

@@ -0,0 +1,175 @@
+# YARD-Lint Configuration
+# See https://github.com/mensfeld/yard-lint for documentation
+
+# Global settings for all validators
+AllValidators:
+  # YARD command-line options (applied to all validators by default)
+  YardOptions:
+    # - --private
+    # - --protected
+
+  # Global file exclusion patterns
+  Exclude:
+    - '\.git'
+    - 'vendor/**/*'
+    - 'node_modules/**/*'
+    - 'spec/**/*'
+    - 'test/**/*'
+    - 'config/db/**/*'
+
+  # Exit code behavior (error, warning, convention, never)
+  FailOnSeverity: warning
+
+  # Minimum documentation coverage percentage (0-100)
+  # Fails if coverage is below this threshold
+  # MinCoverage: 80.0
+
+  # Diff mode settings
+  DiffMode:
+    # Default base ref for --diff (auto-detects main/master if not specified)
+    DefaultBaseRef: ~
+
+# Documentation validators
+Documentation/UndocumentedObjects:
+  Description: 'Checks for classes, modules, and methods without documentation.'
+  Enabled: true
+  Severity: warning
+  ExcludedMethods:
+    - 'initialize/0'  # Exclude parameter-less initialize
+    - '/^_/'          # Exclude private methods (by convention)
+
+Documentation/UndocumentedMethodArguments:
+  Description: 'Checks for method parameters without @param tags.'
+  Enabled: true
+  Severity: warning
+
+Documentation/UndocumentedBooleanMethods:
+  Description: 'Checks that question mark methods document their boolean return.'
+  Enabled: true
+  Severity: warning
+
+Documentation/UndocumentedOptions:
+  Description: 'Detects methods with options hash parameters but no @option tags.'
+  Enabled: true
+  Severity: warning
+
+Documentation/MarkdownSyntax:
+  Description: 'Detects common markdown syntax errors in documentation.'
+  Enabled: true
+  Severity: warning
+
+# Tags validators
+Tags/Order:
+  Description: 'Enforces consistent ordering of YARD tags.'
+  Enabled: true
+  Severity: convention
+  EnforcedOrder:
+    - param
+    - option
+    - return
+    - raise
+    - example
+
+Tags/InvalidTypes:
+  Description: 'Validates type definitions in @param, @return, @option tags.'
+  Enabled: true
+  Severity: warning
+  ValidatedTags:
+    - param
+    - option
+    - return
+
+Tags/TypeSyntax:
+  Description: 'Validates YARD type syntax using YARD parser.'
+  Enabled: true
+  Severity: warning
+  ValidatedTags:
+    - param
+    - option
+    - return
+    - yieldreturn
+
+Tags/MeaninglessTag:
+  Description: 'Detects @param/@option tags on classes, modules, or constants.'
+  Enabled: true
+  Severity: warning
+  CheckedTags:
+    - param
+    - option
+  InvalidObjectTypes:
+    - class
+    - module
+    - constant
+
+Tags/CollectionType:
+  Description: 'Validates Hash collection syntax consistency.'
+  Enabled: true
+  Severity: convention
+  EnforcedStyle: long  # 'long' for Hash{K => V} (YARD standard), 'short' for {K => V}
+  ValidatedTags:
+    - param
+    - option
+    - return
+    - yieldreturn
+
+Tags/TagTypePosition:
+  Description: 'Validates type annotation position in tags.'
+  Enabled: true
+  Severity: convention
+  CheckedTags:
+    - param
+    - option
+  # EnforcedStyle: 'type_after_name' (YARD standard: @param name [Type])
+  #                or 'type_first' (@param [Type] name)
+  EnforcedStyle: type_after_name
+
+Tags/ApiTags:
+  Description: 'Enforces @api tags on public objects.'
+  Enabled: false  # Opt-in validator
+  Severity: warning
+  AllowedApis:
+    - public
+    - private
+    - internal
+
+Tags/OptionTags:
+  Description: 'Requires @option tags for methods with options parameters.'
+  Enabled: true
+  Severity: warning
+
+# Warnings validators - catches YARD parser errors
+Warnings/UnknownTag:
+  Description: 'Detects unknown YARD tags.'
+  Enabled: true
+  Severity: error
+
+Warnings/UnknownDirective:
+  Description: 'Detects unknown YARD directives.'
+  Enabled: true
+  Severity: error
+
+Warnings/InvalidTagFormat:
+  Description: 'Detects malformed tag syntax.'
+  Enabled: true
+  Severity: error
+
+Warnings/InvalidDirectiveFormat:
+  Description: 'Detects malformed directive syntax.'
+  Enabled: true
+  Severity: error
+
+Warnings/DuplicatedParameterName:
+  Description: 'Detects duplicate @param tags.'
+  Enabled: true
+  Severity: error
+
+Warnings/UnknownParameterName:
+  Description: 'Detects @param tags for non-existent parameters.'
+  Enabled: true
+  Severity: error
+
+# Semantic validators
+Semantic/AbstractMethods:
+  Description: 'Ensures @abstract methods do not have real implementations.'
+  Enabled: true
+  Severity: warning

Gemfile

@@ -217,3 +217,5 @@ gem "csv", "~> 3.3"
 gem "arel_extensions", "~> 2.3"
 
 gem "assimp-ffi", git: "https://github.com/Kerilk/assimp-ruby.git"
+
+gem "yard-lint", "~> 1.2", group: :development

Gemfile.lock

@@ -924,6 +924,10 @@ GEM
       activerecord (>= 7.0)
     xpath (3.2.0)
       nokogiri (~> 1.8)
+    yard (0.9.37)
+    yard-lint (1.2.3)
+      yard (~> 0.9)
+      zeitwerk (~> 2.6)
     zeitwerk (2.7.3)
     zxcvbn (0.1.10)
 
@@ -1055,6 +1059,7 @@ DEPENDENCIES
   web-console (~> 4.1)
   webmock (~> 3.26)
   with_model (~> 2.2)
+  yard-lint (~> 1.2)
 
 CHECKSUMS
   actioncable (8.0.2.1) sha256=6f1cb20db39fba28a93569e8d5dab42b2749d7ddd4baebb5bbecd4217e49d6a2
@@ -1397,6 +1402,8 @@ CHECKSUMS
   websocket-extensions (0.1.5) sha256=1c6ba63092cda343eb53fc657110c71c754c56484aad42578495227d717a8241
   with_model (2.2.0) sha256=eb0f498752391917e8c0a990951a343756bb89df2d12190faa5915a3fd99277e
   xpath (3.2.0) sha256=6dfda79d91bb3b949b947ecc5919f042ef2f399b904013eb3ef6d20dd3a4082e
+  yard (0.9.37) sha256=a6e910399e78e613f80ba9add9ba7c394b1a935f083cccbef82903a3d2a26992
+  yard-lint (1.2.3) sha256=d34b963d6dfa71417fc8dbd3a87743f730780bd94f1abba08290d12e97ce5554
   zeitwerk (2.7.3) sha256=b2e86b4a9b57d26ba68a15230dcc7fe6f040f06831ce64417b0621ad96ba3e85
   zxcvbn (0.1.10) sha256=46e49a7cadcaab543b0073715341607ed99ffcacfc96d6f883bf1bfefaf0aaa5