Issue:
Bug: Consider adding `#![forbid(unsafe_code)]`



[Here](https://github.com/juspay/orca/blob/main/crates/router/src/lib.rs) and in any other crate roots it's better to declare `#![forbid(unsafe_code)]` as we do in `masking` crate. This will ease a life of readers and auditors a lot, and will require quite a reasoning for those who will intend to contribute any `unsafe` code.

Pull request description:
## Motivation and Context
Closes #108 

## How did you test it?
Manual, compiler-guided.

## Checklist
- [x] I formatted the code `cargo +nightly fmt`
- [x] I addressed lints thrown by `cargo clippy`
- [x] I reviewed submitted code


Testing:
Manual, compiler-guided.

Patch:
diff --git a/crates/api_models/src/lib.rs b/crates/api_models/src/lib.rs
index e5a864c7a45..84453c1d08a 100644
--- a/crates/api_models/src/lib.rs
+++ b/crates/api_models/src/lib.rs
@@ -1,3 +1,4 @@
+#![forbid(unsafe_code)]
 pub mod admin;
 pub mod bank_accounts;
 pub mod cards;
diff --git a/crates/common_utils/src/lib.rs b/crates/common_utils/src/lib.rs
index 85cdbfe8072..f43102215e1 100644
--- a/crates/common_utils/src/lib.rs
+++ b/crates/common_utils/src/lib.rs
@@ -1,3 +1,4 @@
+#![forbid(unsafe_code)]
 #![warn(
     missing_docs,
     rust_2018_idioms,
diff --git a/crates/redis_interface/src/lib.rs b/crates/redis_interface/src/lib.rs
index 6dc4e0a57dd..f9ce4375417 100644
--- a/crates/redis_interface/src/lib.rs
+++ b/crates/redis_interface/src/lib.rs
@@ -1,3 +1,4 @@
+#![forbid(unsafe_code)]
 // TODO: Add crate & modules documentation for this crate
 
 pub mod commands;
diff --git a/crates/router/src/lib.rs b/crates/router/src/lib.rs
index de83d4e94ff..871fc621c2a 100644
--- a/crates/router/src/lib.rs
+++ b/crates/router/src/lib.rs
@@ -1,3 +1,4 @@
+#![forbid(unsafe_code)]
 // FIXME: I strongly advise to add this worning.
 // #![warn(missing_docs)]
 
diff --git a/crates/router_derive/src/lib.rs b/crates/router_derive/src/lib.rs
index 8e6240d3487..7bb020f3c13 100644
--- a/crates/router_derive/src/lib.rs
+++ b/crates/router_derive/src/lib.rs
@@ -1,5 +1,5 @@
 //! Utility macros for the `router` crate.
-
+#![forbid(unsafe_code)]
 #![warn(missing_docs)]
 
 mod macros;
diff --git a/crates/router_env/src/lib.rs b/crates/router_env/src/lib.rs
index 93eab6e2dcf..6c6ce4893b7 100644
--- a/crates/router_env/src/lib.rs
+++ b/crates/router_env/src/lib.rs
@@ -1,3 +1,4 @@
+#![forbid(unsafe_code)]
 #![warn(
     missing_docs,
     rust_2018_idioms,