refactor: remove pricing field from TPMJS specification

Remove pricing field from the entire project as it doesn't make sense for tool metadata:

- Remove TpmjsPricingSchema and TpmjsPricing type from types package
- Remove pricing from TpmjsRichSchema validation
- Remove pricing from validateTpmjsField check
- Remove pricing documentation from /spec page
- Remove pricing examples from /publish page
- Remove pricing from HOW_TO_PUBLISH_A_TOOL.md
- Remove pricing from @tpmjs/createblogpost example package.json

The pricing field was removed from Tier 3 (Rich) metadata as it's not relevant for tool discovery and integration. Tools can document pricing in their README or documentation links instead.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

packages/tools/createBlogPost/package.json

@@ -84,9 +84,6 @@
       "required": false,
       "type": "api-key"
     },
-    "pricing": {
-      "model": "free"
-    },
     "frameworks": ["vercel-ai", "langchain"],
     "links": {
       "documentation": "https://tpmjs.com/tools/createblogpost",

packages/types/src/tpmjs.ts

@@ -55,17 +55,6 @@ export const TpmjsAuthenticationSchema = z.object({
 
 export type TpmjsAuthentication = z.infer<typeof TpmjsAuthenticationSchema>;
 
-/**
- * Pricing information schema
- */
-export const TpmjsPricingSchema = z.object({
-  model: z.enum(['free', 'freemium', 'paid', 'enterprise']),
-  freeLimit: z.string().optional(),
-  paidUrl: z.string().url().optional(),
-});
-
-export type TpmjsPricing = z.infer<typeof TpmjsPricingSchema>;
-
 /**
  * External links schema
  */
@@ -111,7 +100,6 @@ export const TpmjsRichSchema = TpmjsMinimalSchema.extend({
   parameters: z.array(TpmjsParameterSchema).optional(),
   returns: TpmjsReturnsSchema.optional(),
   authentication: TpmjsAuthenticationSchema.optional(),
-  pricing: TpmjsPricingSchema.optional(),
   frameworks: z
     .array(z.enum(['vercel-ai', 'langchain', 'llamaindex', 'haystack', 'semantic-kernel']))
     .optional(),
@@ -151,7 +139,6 @@ export function validateTpmjsField(tpmjs: unknown): ValidationResult {
       data.parameters ||
       data.returns ||
       data.authentication ||
-      data.pricing ||
       data.frameworks ||
       data.links ||
       data.tags ||