fix: use --data-urlencode for form-urlencoded curl snippets

[HugoHSun]

🚥 Resolves CX-2935

🧰 Changes

Curl snippets for application/x-www-form-urlencoded endpoints were using --data instead of --data-urlencode. This meant values with special characters (spaces, ampersands, etc.) would break when copy-paste and execute in a terminal.

The old code only checked if the param name needed encoding and picked the flag based on that, while ignoring the value. The fix: always use --data-urlencode for form-urlencoded params. It behaves identically to --data when there's nothing to encode, so no downside. Note that the form data values are never pre-encoded though, since oas-to-har just calls String() on them.

This only affects the code snippet shown to developers, the "Try It" executor uses fetch-har with URLSearchParams which already encodes correctly.

🧬 QA & Testing

Find an endpoint with application/x-www-form-urlencoded content type, check that the curl snippet uses --data-urlencode instead of --data

Correct Example

curl --request POST \
  --url https://httpbin.org/anything \
  --header 'content-type: application/x-www-form-urlencoded' \
  --data-urlencode 'foo=bar' \
  --data-urlencode 'query=hello world' \
  --data-urlencode 'filter=status=active&type=user'

{
  "args": {}, 
  "data": "", 
  "files": {}, 
  "form": {
    "filter": "status=active&type=user", 
    "foo": "bar", 
    "query": "hello world"
  }, 
  "headers": {
    "Accept": "*/*", 
    "Content-Length": "62", 
    "Content-Type": "application/x-www-form-urlencoded", 
    "Host": "httpbin.org", 
    "User-Agent": "curl/8.7.1", 
    "X-Amzn-Trace-Id": "Root=1-69942c21-2119bf28086765883dfaa673"
  }, 
  "json": null, 
  "method": "POST", 
  "origin": "1.1.1.1", 
  "url": "https://httpbin.org/anything"
}

Incorrect Example

curl --request POST \
  --url https://httpbin.org/anything \
  --header 'content-type: application/x-www-form-urlencoded' \
  --data 'foo=bar' \
  --data 'query=hello world' \
  --data 'filter=status=active&type=user'

{
  "args": {}, 
  "data": "", 
  "files": {}, 
  "form": {
    "filter": "status=active", 
    "foo": "bar", 
    "query": "hello world", 
    "type": "user"
  }, 
  "headers": {
    "Accept": "*/*", 
    "Content-Length": "56", 
    "Content-Type": "application/x-www-form-urlencoded", 
    "Host": "httpbin.org", 
    "User-Agent": "curl/8.7.1", 
    "X-Amzn-Trace-Id": "Root=1-69942d09-4ad6930b09907b011e840bec"
  }, 
  "json": null, 
  "method": "POST", 
  "origin": "1.1.1.1", 
  "url": "https://httpbin.org/anything"
}