Merge pull request #1172: Update color config entries on workflow config file reference page

Author: victorlin

docs/src/reference/change_log.md

@@ -5,6 +5,8 @@ We also use this change log to document new features that maintain backward comp
 
 ## New features since last version update
 
+- 10 February 2025: Improve documentation regarding custom color map files.
+
 ## v16 (29 January 2025)
 
 - 23 January 2025: Include a new `mlr_lineage_fitness` coloring. This uses live estimates of lineage fitness from [nextstrain.org/sars-cov-2/forecasts](https://nextstrain.org/sars-cov-2/forecasts) to provide a strain-level coloring to the tree. The lineage fitness estimates are automatically updated as new data comes in and so this coloring should stay current. [PR 1169](https://github.com/nextstrain/ncov/pull/1169)

docs/src/reference/workflow-config-file.rst

@@ -152,7 +152,7 @@ colors
 ~~~~~~
 
 - type: string
-- description: Path to a build-specific color map to use in Auspice.
+- description: Path to a build-specific color map file. Format: tab-delimited, no header. Each row should contain a metadata field as the first column, metadata value in the second column, and hex color code in the third column.
 
 .. _configuration-builds-description:
 
@@ -547,6 +547,14 @@ color_schemes
 - default: ``defaults/color_schemes.tsv``
 - used in rules: ``colors``
 
+colors
+~~~~~~
+
+- type: string
+- description: Path to a color map file. Format: tab-delimited, no header. Each row should contain a metadata field as the first column, metadata value in the second column, and hex color code in the third column.
+- default: colors generated from the ``colors`` rule
+- used in rules: ``export``
+
 .. _auspice_config-1:
 
 auspice_config