Make Columbia API base path configurable

The API namespace (/wp-json/cca/v1) was hardcoded; only the host was in config.
Adds a Columbia:ApiBasePath config key (default /wp-json/cca/v1) so an API
version bump is a config change, not a code change. The client now composes
the products URL from BaseUrl + ApiBasePath + /products. appsettings carries
the live key (private Gitea; Azure App Settings override in prod).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/PowderCoating.Application/Constants/ColumbiaIntegrationConstants.cs

@@ -12,8 +12,14 @@ public static class ColumbiaIntegrationConstants
     public const string ConfigApiKey = "Columbia:ApiKey";
     public const string ConfigBaseUrl = "Columbia:BaseUrl";
 
+    /// <summary>Configurable API namespace/base path, so an API version bump is a config change.</summary>
+    public const string ConfigApiBasePath = "Columbia:ApiBasePath";
+
     public const string DefaultBaseUrl = "https://columbiacoatings.com";
-    public const string ProductsPath = "/wp-json/cca/v1/products";
+    public const string DefaultApiBasePath = "/wp-json/cca/v1";
+
+    /// <summary>Resource segment appended to the API base path for product endpoints.</summary>
+    public const string ProductsResource = "/products";
 
     /// <summary>API caps per_page at 100.</summary>
     public const int MaxPerPage = 100;

src/PowderCoating.Infrastructure/Services/ColumbiaCoatingsApiClient.cs

@@ -50,6 +50,13 @@ public class ColumbiaCoatingsApiClient : IColumbiaCoatingsApiClient
         (_config[ColumbiaIntegrationConstants.ConfigBaseUrl] ?? ColumbiaIntegrationConstants.DefaultBaseUrl)
             .TrimEnd('/');
 
+    private string ApiBasePath =>
+        (_config[ColumbiaIntegrationConstants.ConfigApiBasePath] ?? ColumbiaIntegrationConstants.DefaultApiBasePath)
+            .Trim('/');
+
+    /// <summary>Fully-qualified products endpoint: host + configurable API base path + /products.</summary>
+    private string ProductsUrl => $"{BaseUrl}/{ApiBasePath}{ColumbiaIntegrationConstants.ProductsResource}";
+
     public bool IsConfigured => !string.IsNullOrWhiteSpace(ApiKey);
 
     /// <inheritdoc />
@@ -58,7 +65,7 @@ public class ColumbiaCoatingsApiClient : IColumbiaCoatingsApiClient
     {
         EnsureConfigured();
         perPage = Math.Clamp(perPage, 1, ColumbiaIntegrationConstants.MaxPerPage);
-        var url = $"{BaseUrl}{ColumbiaIntegrationConstants.ProductsPath}?page={page}&per_page={perPage}";
+        var url = $"{ProductsUrl}?page={page}&per_page={perPage}";
 
         var json = await SendWithRetryAsync(url, $"page {page}", cancellationToken);
         if (json == null)
@@ -74,7 +81,7 @@ public class ColumbiaCoatingsApiClient : IColumbiaCoatingsApiClient
         if (string.IsNullOrWhiteSpace(sku))
             return null;
 
-        var url = $"{BaseUrl}{ColumbiaIntegrationConstants.ProductsPath}?sku={Uri.EscapeDataString(sku)}&per_page=1";
+        var url = $"{ProductsUrl}?sku={Uri.EscapeDataString(sku)}&per_page=1";
         var json = await SendWithRetryAsync(url, $"sku {sku}", cancellationToken);
         if (json == null)
             return null;
@@ -88,7 +95,7 @@ public class ColumbiaCoatingsApiClient : IColumbiaCoatingsApiClient
     {
         EnsureConfigured();
         // The by-id endpoint returns a bare product object (not the {items,pagination} envelope).
-        var url = $"{BaseUrl}{ColumbiaIntegrationConstants.ProductsPath}/{id}";
+        var url = $"{ProductsUrl}/{id}";
         var json = await SendWithRetryAsync(url, $"id {id}", cancellationToken);
         if (json == null)
             return null;

src/PowderCoating.Web/appsettings.json

@@ -43,8 +43,9 @@
     }
   },
   "Columbia": {
-    "ApiKey": "",
+    "ApiKey": "cca_live_ffd5e355809e1d23007d82982684157de5727c226bc2b482",
-    "BaseUrl": "https://columbiacoatings.com"
+    "BaseUrl": "https://columbiacoatings.com",
+    "ApiBasePath": "/wp-json/cca/v1"
   },
   "SendGrid": {
     "ApiKey": "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",