feat: add data classes for proposal response

This commit introduces data classes to represent proposal responses:

- `Status`: Represents the status of a proposal with a
 code and value.
- `ProposalData`: Represents a single proposal with details like message, CV, status, job ID, amount, ID, and user ID.

app/src/main/java/com/samuelokello/kazihub/domain/model/proposal/proposalResponse/Proposal.kt

@@ -0,0 +1,21 @@
+package com.samuelokello.kazihub.domain.model.proposal.proposalResponse
+
+
+import com.google.gson.annotations.SerializedName
+
+data class ProposalData(
+    @SerializedName("message")
+    val message: String?,
+    @SerializedName("cv")
+    val cv: String,
+    @SerializedName("status")
+    val status: Status,
+    @SerializedName("job_id")
+    val jobId: Int,
+    @SerializedName("amount")
+    val amount: Double,
+    @SerializedName("id")
+    val id: Int,
+    @SerializedName("user_id")
+    val userId: Int
+)

app/src/main/java/com/samuelokello/kazihub/domain/model/proposal/proposalResponse/Status.kt

@@ -0,0 +1,11 @@
+package com.samuelokello.kazihub.domain.model.proposal.proposalResponse
+
+
+import com.google.gson.annotations.SerializedName
+
+data class Status(
+    @SerializedName("code")
+    val code: String,
+    @SerializedName("value")
+    val value: String
+)