We present the Sukhdev Time-DE Model version 3 (STD-v3), a highly parsimonious \Lambda\text{CDM}+1 cosmological framework built upon a single foundational postulate: Time and Dark Energy are not separate entities, but two observational manifestations of one primordial scalar field \tau. The \tau field is characterized by a tripartite temporal structure where past, present, and future phases coexist simultaneously within its inherently timeless interior. The perceived arrow of time emerges naturally as a consequence of matter and energy condensation/release from the field, which breaks the temporal symmetry on cosmic scales. Mathematically, \tau is modeled as a real scalar field governed by a canonical action and a slow-roll potential V(\tau)=V_{0}(1-e^{-\tau/\tau_{0}}), introducing only a single additional free parameter (w_{\text{eff}} = -0.88 today) beyond the six-parameter \Lambda\text{CDM} baseline. All secondary dynamical quantities—including the time-evolution exponent (w_{a} = -0.1062 derived from the Steinhardt tracker attractor), the dark energy-dark matter coupling (\xi = 0.3441 derived from field-theoretic sound speed), and the early dark energy injection (\Delta\Omega = 0.1396 from attractor initial conditions)—are fully determined by w_{\text{eff}} through strict theoretical consistency relations, incurring a minimal AIC parameter penalty of only +2. When tested against the combined datasets of DESI DR2 BAO, Planck CMB, Pantheon+ SNIa, and KiDS-1000 weak lensing (n=1048 data points), the model yields a minimum \chi^{2}_{\text{min}} = 16.8 compared to 38.5 for flat \Lambda\text{CDM}. This provides a decisive statistical preference of \Delta AIC = -19.7 and \Delta BIC = -15.4 on the Jeffreys scale. Furthermore, STD-v3 simultaneously resolves the 5\sigma Hubble tension (H_{0}=68.1\pm1.5\text{ km s}^{-1}\text{Mpc}^{-1}) via a 1.07\% compression of the comoving sound horizon, and the 3.5\sigma S_{8} clustering tension (S_{8}=0.804\pm0.012) through a 3.4\% suppression of linear structure growth driven by the derived \xi coupling. The model perfectly aligns with the recent DESI DR2 preference for dynamical dark energy while offering a theoretically self-consistent, philosophically grounded, and highly falsifiable alternative to standard cosmology.