docs: add Sol model discount pricing

packages/web/src/content/docs/zen.mdx

@@ -188,8 +188,8 @@ We support a pay-as-you-go model. Below are the prices **per 1M tokens**.
 | Grok 4.5 (≤ 200K tokens)          | $2.00  | $6.00   | $0.30       | -            |
 | Grok 4.5 (> 200K tokens)          | $4.00  | $12.00  | $0.60       | -            |
 | Grok Build 0.1                    | $1.00  | $2.00   | $0.20       | -            |
-| GPT 5.6 Sol (≤ 272K tokens)       | $5.00  | $30.00  | $0.50       | $6.25        |
-| GPT 5.6 Sol (> 272K tokens)       | $10.00 | $45.00  | $1.00       | $12.50       |
+| GPT 5.6 Sol (50% off, ≤ 272K tokens) | ~~$5.00~~ $2.50  | ~~$30.00~~ $15.00  | ~~$0.50~~ $0.25       | ~~$6.25~~ $3.125        |
+| GPT 5.6 Sol (50% off, > 272K tokens) | ~~$10.00~~ $5.00 | ~~$45.00~~ $22.50  | ~~$1.00~~ $0.50       | ~~$12.50~~ $6.25       |
 | GPT 5.6 Terra (≤ 272K tokens)     | $2.00  | $12.00  | $0.20       | $2.50        |
 | GPT 5.6 Terra (> 272K tokens)     | $4.00  | $18.00  | $0.40       | $5.00        |
 | GPT 5.6 Luna (≤ 272K tokens)      | $0.20  | $1.20   | $0.02       | $0.25        |