⬆️ 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/obiseq/taxonomy_lca.md

@@ -0,0 +1,22 @@
+# Taxonomic Analysis Functions in `obiseq` Package
+
+This module provides tools for assigning taxonomic labels to biological sequences using a reference taxonomy.
+
+- **`TaxonomicDistribution(taxonomy)`**:  
+  Returns a map from taxonomic nodes to read counts, based on `taxid` annotations in the sequence metadata. It validates taxids against the taxonomy and enforces strict handling of aliases.
+
+- **`LCA(taxonomy, threshold)`**:  
+  Computes the *Lowest Common Ancestor* (LCA) of all taxonomic assignments for a sequence, weighted by their abundances.  
+  - Iteratively traverses upward from each taxon’s path in the taxonomy tree.  
+  - At each level, computes the relative weight (`rmax`) of the most frequent taxon.  
+  - Stops when `rmax < threshold`, returning:  
+    • the LCA taxon,  
+    • its confidence score (`rans`), and  
+    • total read count used.
+
+- **`AddLCAWorker(...)`**:  
+  Creates a `SeqWorker` function to annotate sequences with LCA results:  
+    - Sets attributes like `<slot>_taxid`, `<slot>_name`, and `<slot>_error` (rounded to 3 decimals).  
+    - Automatically appends `_taxid` if missing in `slot_name`.  
+
+All functions integrate with the OBITools4 ecosystem, supporting robust taxonomic inference for metabarcoding workflows.