Feat: adding new non-mandatory fields.

As per title

app/forms/project.py

@@ -14,20 +14,54 @@ from wtforms.validators import DataRequired, ValidationError
 class ProjectForm(FlaskForm):
     title = StringField("Title", validators=[DataRequired()])
     description = TextAreaField("Description", validators=[DataRequired()])
+    background_skills = TextAreaField("Background skills")
     is_student_proposal = BooleanField("Student Proposal", default=False)
     on_behalf = StringField("from", default=None)
     category = SelectField("Category", coerce=str)
+    meeting_modes = [("", "N/A"), ("remote", "Remote"), ("in-person", "In person")]
     meeting_mode = SelectField(
         "Meeting type",
-        choices=[("", "N/A"), ("remote", "Remote"), ("in-person", "In person")],
+        choices=meeting_modes,
         coerce=str,
-        validators=[validators.Optional()],
+        validators=[
+            validators.Optional(),
+            validators.AnyOf([c[0] for c in meeting_modes]),
+        ],
     )
     proposed_start_date = DateField(
         "Proposed start date", validators=[validators.Optional()]
     )
     duration_in_weeks = IntegerField(
-        "Duration (in weeks)", validators=[validators.Optional()]
+        "Duration (in weeks)",
+        validators=[validators.Optional(), validators.NumberRange(min=0)],
+    )
+    time_commitments = [
+        ("", "N/A"),
+        ("full-time", "Full-time"),
+        ("part-time", "Part-time"),
+    ]
+    time_commitment = SelectField(
+        "Time Commitment",
+        choices=time_commitments,
+        coerce=str,
+        validators=[
+            validators.Optional(),
+            validators.AnyOf([c[0] for c in time_commitments]),
+        ],
+    )
+    lab_usages = [
+        ("", "N/A"),
+        ("lab-based", "Lab-based project"),
+        ("non-lab-based", "Not lab-based"),
+    ]
+    lab_usage = SelectField(
+        "Lab usage",
+        choices=lab_usages,
+        coerce=str,
+        validators=[
+            validators.Optional(),
+            validators.AnyOf([c[0] for c in lab_usages]),
+        ],
     )
 
     def validate_on_behalf(self, field):
@@ -40,19 +74,3 @@ class ProjectForm(FlaskForm):
         if field == self.category and field.data == "":
             self.category.errors += "Please choose a category for the project."
             raise ValidationError("Please choose a category for the project.")
-
-    def validate_meeting_mode(self, field):
-        if field == self.category and field.data not in ["", "remote", "in-person"]:
-            self.meeting_mode.errors += "Invalid meeting mode."
-            raise ValidationError(
-                "The meeting mode for the project is invalid. Choose a valid value or leave it blank."
-            )
-
-    def validate_duration(self, field):
-        if all(
-            (field == self.duration_in_weeks, field.data is not None, field.data < 0)
-        ):
-            self.meeting_mode.errors += "Invalid duration."
-            raise ValidationError(
-                "The duration for the project is invalid. Choose a valid value or leave it blank."
-            )