Frontend Integration: Execute Soroban create_stream Transaction #176

[CMI-James]

Description

Connect the dashboard "Create Stream" form to Freighter so form submission signs and submits a Soroban create_stream transaction through the existing contract client.

Closes #176

Changes proposed

What were you told to do?

I was asked to connect the "Create Stream" UI to the Freighter wallet so that submitting the form prompts wallet signing and submits a create_stream transaction to the Soroban smart contract.

What did I do?

Wired dashboard form submission to Soroban/Freighter transaction flow

• Replaced placeholder alert(...) behavior in handleFormCreateStream with real transaction submission.
• Validates required fields, recipient address format, and start/end datetime order.
• Computes duration in seconds from startsAt/endsAt and maps form data to the existing handleCreateStream contract flow.
• Uses existing Soroban helpers (toBaseUnits, toDurationSeconds, getTokenAddress, sorobanCreateStream) so the submit action uses Freighter signing + Soroban submit path.

Restored full stream form controls in the Streams tab

• Added/connected fields required for real submission:
  • Total Amount
  • Starts At
  • Ends At
  • Cadence (seconds)
  • Note
• Added form actions:
  • Create Stream submit button
  • Reset button
• Added isFormSubmitting state to prevent duplicate submissions while wallet/network flow is in progress.

Check List (Check all the applicable boxes)

• My code follows the code style of this project.
• This PR does not contain plagiarized content.
• The title and description of the PR is clear and explains the approach.
• I am making a pull request against the main branch (left side).
• My commit messages styles matches our requested structure.
• My code additions will fail neither code linting checks nor unit test.
• I am only making changes to files I was requested to.

Screenshots / Testing Evidence

Validated with:

Manual code-path validation of dashboard form -> `handleCreateStream` -> Soroban helper flow.

Note: lint/test commands were not executed in this environment because eslint was unavailable locally (sh: eslint: command not found).