⬆️ version bump to v4.5

- Update obioptions.Version from "Release 4.4.29" to "/v/ Release v5"
- Update version.txt from 4.29 → .30
(automated by Makefile)

autodoc/docmd/pkg/obitax/taxonnode.md

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+# `obitax` Package: Taxonomic Node Representation and Management
+
+The `obitax` package provides a lightweight, pointer-based Go implementation for representing taxonomic nodes in biological classification systems.
+
+## Core Data Structure
+
+- **`TaxNode`**: Represents a single taxon (e.g., species, genus) with the following fields:
+  - `id`: Unique taxon identifier (pointer to string).
+  - `parent`: Identifier of the parent node in the taxonomy hierarchy.
+  - `rank`: Taxonomic rank (e.g., `"species"`, `"family"`).
+  - `scientificname`: Canonical scientific name (e.g., *Homo sapiens*).
+  - `alternatenames`: Map of alternative names keyed by name class (e.g., `"common_name"`, `"synonym"`).
+
+## Key Functionalities
+
+- **String Representation**  
+  `String(taxonomyCode)` returns a formatted label like `"NCBI:12345 [Homo sapiens]@species"` (or raw ID if enabled via `obidefault.UseRawTaxids()`).
+
+- **Accessors**  
+  - `Id()`, `ParentId()`: Retrieve identifiers.
+  - `ScientificName()` / `Rank()`: Return name or rank (defaulting to `"NA"` if missing).
+  - `Name(class)`: Fetch name by class (`"scientific name"` or alternate).
+
+- **Mutators**  
+  - `SetName(name, class)`: Assign scientific name or add/update alternate names.
+
+- **Name Matching & Validation**  
+  - `IsNameEqual(name, ignoreCase)`: Exact or case-insensitive match against scientific/alternate names.
+  - `IsNameMatching(pattern)`: Regex-based pattern matching over all available names.
+
+## Design Notes
+
+- Uses pointers for optional fields (enables `nil` semantics).
+- Graceful handling of missing data (`NA`, empty strings, safe dereferencing with `nil` checks).
+- Integrates logging via Logrus (`log.Panic` on misuse, e.g., setting name of `nil` node).
+- Designed for use in larger OBITools pipelines (e.g., with `obidefault` configuration).